Release v5.3.3

Remove support for open polymorphic serialization in
kotlinx.serialization web converters and codecs in order
to prevent serialization handling suitable for Jackson
or other general purpose Java JSON libraries.

This will probably need further refinements for collections
for example, and could ultimately be fixed when
kotlinx.serialization will provide a dedicated function to
evaluate upfront if a type can be serialized or not.

Closes gh-26298

README.md

@@ -1,4 +1,4 @@
-# <img src="src/docs/spring-framework.png" width="80" height="80"> Spring Framework [![Build Status](https://ci.spring.io/api/v1/teams/spring-framework/pipelines/spring-framework-5.3.x/jobs/build/badge)](https://ci.spring.io/teams/spring-framework/pipelines/spring-framework-5.3.x?groups=Build")
+# <img src="src/docs/spring-framework.png" width="80" height="80"> Spring Framework [![Build Status](https://ci.spring.io/api/v1/teams/spring-framework/pipelines/spring-framework-5.3.x/jobs/build/badge)](https://ci.spring.io/teams/spring-framework/pipelines/spring-framework-5.3.x?groups=Build") [![Revved up by Gradle Enterprise](https://img.shields.io/badge/Revved%20up%20by-Gradle%20Enterprise-06A0CE?logo=Gradle&labelColor=02303A)](https://ge.spring.io/scans?search.rootProjectNames=spring)
 
 This is the home of the Spring Framework: the foundation for all [Spring projects](https://spring.io/projects). Collectively the Spring Framework and the family of Spring projects are often referred to simply as "Spring". 
 

build.gradle

@@ -1,7 +1,7 @@
 plugins {
 	id 'io.spring.dependency-management' version '1.0.9.RELEASE' apply false
 	id 'io.spring.nohttp' version '0.0.5.RELEASE'
-	id 'org.jetbrains.kotlin.jvm' version '1.4.10' apply false
+	id 'org.jetbrains.kotlin.jvm' version '1.4.21' apply false
 	id 'org.jetbrains.dokka' version '0.10.1' apply false
 	id 'org.asciidoctor.jvm.convert' version '3.1.0'
 	id 'org.asciidoctor.jvm.pdf' version '3.1.0'
@@ -9,7 +9,7 @@ plugins {
 	id "io.freefair.aspectj" version '5.1.1' apply false
 	id "com.github.ben-manes.versions" version '0.28.0'
 	id "me.champeau.gradle.jmh" version "0.5.0" apply false
-	id "org.jetbrains.kotlin.plugin.serialization" version "1.4.10" apply false
+	id "org.jetbrains.kotlin.plugin.serialization" version "1.4.21" apply false
 }
 
 ext {
@@ -25,18 +25,18 @@ configure(allprojects) { project ->
 
 	dependencyManagement {
 		imports {
-			mavenBom "com.fasterxml.jackson:jackson-bom:2.11.3"
-			mavenBom "io.netty:netty-bom:4.1.53.Final"
-			mavenBom "io.projectreactor:reactor-bom:2020.0.0"
+			mavenBom "com.fasterxml.jackson:jackson-bom:2.12.0"
+			mavenBom "io.netty:netty-bom:4.1.56.Final"
+			mavenBom "io.projectreactor:reactor-bom:2020.0.3"
 			mavenBom "io.r2dbc:r2dbc-bom:Arabba-SR8"
 			mavenBom "io.rsocket:rsocket-bom:1.1.0"
-			mavenBom "org.eclipse.jetty:jetty-bom:9.4.34.v20201102"
-			mavenBom "org.jetbrains.kotlin:kotlin-bom:1.4.10"
-			mavenBom "org.jetbrains.kotlinx:kotlinx-coroutines-bom:1.4.1"
+			mavenBom "org.eclipse.jetty:jetty-bom:9.4.35.v20201120"
+			mavenBom "org.jetbrains.kotlin:kotlin-bom:1.4.21"
+			mavenBom "org.jetbrains.kotlinx:kotlinx-coroutines-bom:1.4.2"
 			mavenBom "org.junit:junit-bom:5.7.0"
 		}
 		dependencies {
-			dependencySet(group: 'org.apache.logging.log4j', version: '2.13.3') {
+			dependencySet(group: 'org.apache.logging.log4j', version: '2.14.0') {
 				entry 'log4j-api'
 				entry 'log4j-core'
 				entry 'log4j-jul'
@@ -53,7 +53,7 @@ configure(allprojects) { project ->
 				entry 'aspectjtools'
 				entry 'aspectjweaver'
 			}
-			dependencySet(group: 'org.codehaus.groovy', version: '3.0.6') {
+			dependencySet(group: 'org.codehaus.groovy', version: '3.0.7') {
 				entry 'groovy'
 				entry 'groovy-jsr223'
 				entry 'groovy-templates'  // requires findbugs for warning-free compilation
@@ -63,8 +63,8 @@ configure(allprojects) { project ->
 
 			dependency "io.reactivex:rxjava:1.3.8"
 			dependency "io.reactivex:rxjava-reactive-streams:1.2.1"
-			dependency "io.reactivex.rxjava2:rxjava:2.2.19"
-			dependency "io.reactivex.rxjava3:rxjava:3.0.7"
+			dependency "io.reactivex.rxjava2:rxjava:2.2.20"
+			dependency "io.reactivex.rxjava3:rxjava:3.0.9"
 			dependency "io.projectreactor.tools:blockhound:1.0.4.RELEASE"
 
 			dependency "com.caucho:hessian:4.0.63"
@@ -73,9 +73,9 @@ configure(allprojects) { project ->
 				exclude group: "stax", name: "stax-api"
 			}
 			dependency "com.google.code.gson:gson:2.8.6"
-			dependency "com.google.protobuf:protobuf-java-util:3.13.0"
+			dependency "com.google.protobuf:protobuf-java-util:3.14.0"
 			dependency "com.googlecode.protobuf-java-format:protobuf-java-format:1.4"
-			dependency("com.thoughtworks.xstream:xstream:1.4.13") {
+			dependency("com.thoughtworks.xstream:xstream:1.4.14") {
 				exclude group: "xpp3", name: "xpp3_min"
 				exclude group: "xmlpull", name: "xmlpull"
 			}
@@ -95,8 +95,8 @@ configure(allprojects) { project ->
 			}
 
 			dependency "com.h2database:h2:1.4.200"
-			dependency "com.github.ben-manes.caffeine:caffeine:2.8.6"
-			dependency "com.github.librepdf:openpdf:1.3.22"
+			dependency "com.github.ben-manes.caffeine:caffeine:2.8.8"
+			dependency "com.github.librepdf:openpdf:1.3.24"
 			dependency "com.rometools:rome:1.15.0"
 			dependency "commons-io:commons-io:2.5"
 			dependency "io.vavr:vavr:0.10.3"
@@ -123,23 +123,23 @@ configure(allprojects) { project ->
 			dependency "net.sf.ehcache:ehcache:2.10.6"
 			dependency "org.ehcache:jcache:1.0.1"
 			dependency "org.ehcache:ehcache:3.4.0"
-			dependency "org.hibernate:hibernate-core:5.4.23.Final"
-			dependency "org.hibernate:hibernate-validator:6.1.6.Final"
+			dependency "org.hibernate:hibernate-core:5.4.27.Final"
+			dependency "org.hibernate:hibernate-validator:6.2.0.Final"
 			dependency "org.webjars:webjars-locator-core:0.46"
 			dependency "org.webjars:underscorejs:1.8.3"
 
-			dependencySet(group: 'org.apache.tomcat', version: '9.0.39') {
+			dependencySet(group: 'org.apache.tomcat', version: '9.0.41') {
 				entry 'tomcat-util'
 				entry('tomcat-websocket') {
 					exclude group: "org.apache.tomcat", name: "tomcat-websocket-api"
 					exclude group: "org.apache.tomcat", name: "tomcat-servlet-api"
 				}
 			}
-			dependencySet(group: 'org.apache.tomcat.embed', version: '9.0.39') {
+			dependencySet(group: 'org.apache.tomcat.embed', version: '9.0.41') {
 				entry 'tomcat-embed-core'
 				entry 'tomcat-embed-websocket'
 			}
-			dependencySet(group: 'io.undertow', version: '2.2.2.Final') {
+			dependencySet(group: 'io.undertow', version: '2.2.3.Final') {
 				entry 'undertow-core'
 				entry('undertow-websockets-jsr') {
 					exclude group: "org.jboss.spec.javax.websocket", name: "jboss-websocket-api_1.1_spec"
@@ -154,15 +154,15 @@ configure(allprojects) { project ->
 				entry 'okhttp'
 				entry 'mockwebserver'
 			}
-			dependency("org.apache.httpcomponents:httpclient:4.5.12") {
+			dependency("org.apache.httpcomponents:httpclient:4.5.13") {
 				exclude group: "commons-logging", name: "commons-logging"
 			}
 			dependency("org.apache.httpcomponents:httpasyncclient:4.1.4") {
 				exclude group: "commons-logging", name: "commons-logging"
 			}
 			dependency 'org.apache.httpcomponents.client5:httpclient5:5.0.3'
-			dependency 'org.apache.httpcomponents.core5:httpcore5-reactive:5.0.2'
-			dependency "org.eclipse.jetty:jetty-reactive-httpclient:1.1.4"
+			dependency 'org.apache.httpcomponents.core5:httpcore5-reactive:5.0.3'
+			dependency "org.eclipse.jetty:jetty-reactive-httpclient:1.1.5"
 
 			dependency "org.jruby:jruby:9.2.13.0"
 			dependency "org.python:jython-standalone:2.7.1"
@@ -190,25 +190,25 @@ configure(allprojects) { project ->
 			dependency "org.testng:testng:7.3.0"
 			dependency "org.hamcrest:hamcrest:2.1"
 			dependency "org.awaitility:awaitility:3.1.6"
-			dependency "org.assertj:assertj-core:3.18.0"
-			dependencySet(group: 'org.xmlunit', version: '2.6.2') {
+			dependency "org.assertj:assertj-core:3.18.1"
+			dependencySet(group: 'org.xmlunit', version: '2.8.2') {
 				entry 'xmlunit-assertj'
 				entry('xmlunit-matchers') {
 					exclude group: "org.hamcrest", name: "hamcrest-core"
 				}
 			}
-			dependencySet(group: 'org.mockito', version: '3.6.0') {
+			dependencySet(group: 'org.mockito', version: '3.7.0') {
 				entry('mockito-core') {
 					exclude group: "org.hamcrest", name: "hamcrest-core"
 				}
 				entry 'mockito-junit-jupiter'
 			}
-			dependency "io.mockk:mockk:1.10.0"
+			dependency "io.mockk:mockk:1.10.2"
 
-			dependency("net.sourceforge.htmlunit:htmlunit:2.44.0") {
+			dependency("net.sourceforge.htmlunit:htmlunit:2.46.0") {
 				exclude group: "commons-logging", name: "commons-logging"
 			}
-			dependency("org.seleniumhq.selenium:htmlunit-driver:2.44.0") {
+			dependency("org.seleniumhq.selenium:htmlunit-driver:2.46.0") {
 				exclude group: "commons-logging", name: "commons-logging"
 			}
 			dependency("org.seleniumhq.selenium:selenium-java:3.141.59") {
@@ -236,7 +236,7 @@ configure(allprojects) { project ->
 
 			dependency "com.ibm.websphere:uow:6.0.2.17"
 			dependency "com.jamonapi:jamon:2.82"
-			dependency "joda-time:joda-time:2.10.6"
+			dependency "joda-time:joda-time:2.10.9"
 			dependency "org.eclipse.persistence:org.eclipse.persistence.jpa:2.7.7"
 			dependency "org.javamoney:moneta:1.3"
 
@@ -339,7 +339,7 @@ configure([rootProject] + javaProjects) { project ->
 	}
 
 	checkstyle {
-		toolVersion = "8.36.2"
+		toolVersion = "8.39"
 		configDirectory.set(rootProject.file("src/checkstyle"))
 	}
 

ci/images/get-jdk-url.sh

@@ -3,16 +3,13 @@ set -e
 
 case "$1" in
 	java8)
-		 echo "https://github.com/AdoptOpenJDK/openjdk8-binaries/releases/download/jdk8u265-b01/OpenJDK8U-jdk_x64_linux_hotspot_8u265b01.tar.gz"
+		 echo "https://github.com/AdoptOpenJDK/openjdk8-binaries/releases/download/jdk8u275-b01/OpenJDK8U-jdk_x64_linux_hotspot_8u275b01.tar.gz"
 	;;
 	java11)
-		 echo "https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11.0.8%2B10/OpenJDK11U-jdk_x64_linux_hotspot_11.0.8_10.tar.gz"
-	;;
-	java14)
-		 echo "https://github.com/AdoptOpenJDK/openjdk14-binaries/releases/download/jdk-14.0.2%2B12/OpenJDK14U-jdk_x64_linux_hotspot_14.0.2_12.tar.gz"
+		 echo "https://github.com/AdoptOpenJDK/openjdk11-binaries/releases/download/jdk-11.0.9.1%2B1/OpenJDK11U-jdk_x64_linux_hotspot_11.0.9.1_1.tar.gz"
 	;;
   java15)
-		 echo "https://github.com/AdoptOpenJDK/openjdk15-binaries/releases/download/jdk-15%2B36/OpenJDK15U-jdk_x64_linux_hotspot_15_36.tar.gz"
+		 echo "https://github.com/AdoptOpenJDK/openjdk15-binaries/releases/download/jdk-15.0.1%2B9/OpenJDK15U-jdk_x64_linux_hotspot_15.0.1_9.tar.gz"
   ;;
   *)
 		echo $"Unknown java version"

ci/images/setup.sh

@@ -5,8 +5,11 @@ set -ex
 # UTILS
 ###########################################################
 
+export DEBIAN_FRONTEND=noninteractive
 apt-get update
-apt-get install --no-install-recommends -y ca-certificates net-tools libxml2-utils git curl libudev1 libxml2-utils iptables iproute2 jq fontconfig
+apt-get install --no-install-recommends -y tzdata ca-certificates net-tools libxml2-utils git curl libudev1 libxml2-utils iptables iproute2 jq fontconfig
+ln -fs /usr/share/zoneinfo/UTC /etc/localtime
+dpkg-reconfigure --frontend noninteractive tzdata
 rm -rf /var/lib/apt/lists/*
 
 curl https://raw.githubusercontent.com/spring-io/concourse-java-scripts/v0.0.3/concourse-java.sh > /opt/concourse-java.sh

ci/images/spring-framework-ci-image/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:bionic-20200713
+FROM ubuntu:focal-20201106
 
 ADD setup.sh /setup.sh
 ADD get-jdk-url.sh /get-jdk-url.sh

ci/images/spring-framework-jdk11-ci-image/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:bionic-20200713
+FROM ubuntu:focal-20201106
 
 ADD setup.sh /setup.sh
 ADD get-jdk-url.sh /get-jdk-url.sh

ci/images/spring-framework-jdk14-ci-image/Dockerfile

@@ -1,8 +0,0 @@
-FROM ubuntu:bionic-20200713
-
-ADD setup.sh /setup.sh
-ADD get-jdk-url.sh /get-jdk-url.sh
-RUN ./setup.sh java14
-
-ENV JAVA_HOME /opt/openjdk
-ENV PATH $JAVA_HOME/bin:$PATH

ci/images/spring-framework-jdk15-ci-image/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:bionic-20200713
+FROM ubuntu:focal-20201106
 
 ADD setup.sh /setup.sh
 ADD get-jdk-url.sh /get-jdk-url.sh

ci/pipeline.yml

@@ -37,17 +37,17 @@ anchors:
 
 resource_types:
 - name: artifactory-resource
-  type: docker-image
+  type: registry-image
   source:
     repository: springio/artifactory-resource
     tag: 0.0.12
 - name: github-status-resource
-  type: docker-image
+  type: registry-image
   source:
     repository: dpb587/github-status-resource
     tag: master
 - name: slack-notification
-  type: docker-image
+  type: registry-image
   source:
     repository: cfcommunity/slack-notification-resource
     tag: latest
@@ -87,12 +87,6 @@ resources:
   source:
     <<: *docker-resource-source
     repository: ((docker-hub-organization))/spring-framework-jdk11-ci-image
-- name: spring-framework-jdk14-ci-image
-  type: docker-image
-  icon: docker
-  source:
-    <<: *docker-resource-source
-    repository: ((docker-hub-organization))/spring-framework-jdk14-ci-image
 - name: spring-framework-jdk15-ci-image
   type: docker-image
   icon: docker
@@ -123,14 +117,6 @@ resources:
     access_token: ((github-ci-status-token))
     branch: ((branch))
     context: jdk11-build
-- name: repo-status-jdk14-build
-  type: github-status-resource
-  icon: eye-check-outline
-  source:
-    repository: ((github-repo-name))
-    access_token: ((github-ci-status-token))
-    branch: ((branch))
-    context: jdk14-build
 - name: repo-status-jdk15-build
   type: github-status-resource
   icon: eye-check-outline
@@ -176,10 +162,6 @@ jobs:
       params:
         build: ci-images-git-repo/ci/images
         dockerfile: ci-images-git-repo/ci/images/spring-framework-jdk11-ci-image/Dockerfile
-    - put: spring-framework-jdk14-ci-image
-      params:
-        build: ci-images-git-repo/ci/images
-        dockerfile: ci-images-git-repo/ci/images/spring-framework-jdk14-ci-image/Dockerfile
     - put: spring-framework-jdk15-ci-image
       params:
         build: ci-images-git-repo/ci/images
@@ -268,34 +250,6 @@ jobs:
           <<: *slack-fail-params
   - put: repo-status-jdk11-build
     params: { state: "success", commit: "git-repo" }
-- name: jdk14-build
-  serial: true
-  public: true
-  plan:
-    - get: spring-framework-jdk14-ci-image
-    - get: git-repo
-    - get: every-morning
-      trigger: true
-    - put: repo-status-jdk14-build
-      params: { state: "pending", commit: "git-repo" }
-    - do:
-      - task: check-project
-        privileged: true
-        timeout: ((task-timeout))
-        image: spring-framework-jdk14-ci-image
-        file: git-repo/ci/tasks/check-project.yml
-        params:
-          BRANCH: ((branch))
-          <<: *gradle-enterprise-task-params
-      on_failure:
-        do:
-          - put: repo-status-jdk14-build
-            params: { state: "failure", commit: "git-repo" }
-          - put: slack-alert
-            params:
-              <<: *slack-fail-params
-    - put: repo-status-jdk14-build
-      params: { state: "success", commit: "git-repo" }
 - name: jdk15-build
   serial: true
   public: true
@@ -480,7 +434,7 @@ jobs:
 
 groups:
 - name: "builds"
-  jobs: ["build", "jdk11-build", "jdk14-build", "jdk15-build"]
+  jobs: ["build", "jdk11-build", "jdk15-build"]
 - name: "releases"
   jobs: ["stage-milestone", "stage-rc", "stage-release", "promote-milestone","promote-rc", "promote-release", "sync-to-maven-central"]
 - name: "ci-images"

ci/scripts/promote-version.sh

@@ -6,11 +6,11 @@ CONFIG_DIR=git-repo/ci/config
 version=$( cat artifactory-repo/build-info.json | jq -r '.buildInfo.modules[0].id' | sed 's/.*:.*:\(.*\)/\1/' )
 export BUILD_INFO_LOCATION=$(pwd)/artifactory-repo/build-info.json
 
-java -jar /opt/concourse-release-scripts.jar promote $RELEASE_TYPE $BUILD_INFO_LOCATION > /dev/null || { exit 1; }
+java -jar /opt/concourse-release-scripts.jar promote $RELEASE_TYPE $BUILD_INFO_LOCATION || { exit 1; }
 
 java -jar /opt/concourse-release-scripts.jar \
   --spring.config.location=${CONFIG_DIR}/release-scripts.yml \
-  distribute $RELEASE_TYPE $BUILD_INFO_LOCATION > /dev/null || { exit 1; }
+  distribute $RELEASE_TYPE $BUILD_INFO_LOCATION || { exit 1; }
 
 echo "Promotion complete"
 echo $version > version/version

gradle.properties

@@ -1,4 +1,4 @@
-version=5.3.1
+version=5.3.3
 org.gradle.jvmargs=-Xmx1536M
 org.gradle.caching=true
 org.gradle.parallel=true

gradle/docs.gradle

@@ -3,7 +3,7 @@ configurations {
 }
 
 dependencies {
-	asciidoctorExt("io.spring.asciidoctor:spring-asciidoctor-extensions-block-switch:0.4.3.RELEASE")
+	asciidoctorExt("io.spring.asciidoctor:spring-asciidoctor-extensions-block-switch:0.5.0")
 }
 
 repositories {
@@ -113,7 +113,7 @@ dokka {
 }
 
 task downloadResources(type: Download) {
-	def version = "0.2.2.RELEASE"
+	def version = "0.2.5"
 	src "https://repo.spring.io/release/io/spring/docresources/" +
 			"spring-doc-resources/$version/spring-doc-resources-${version}.zip"
 	dest project.file("$buildDir/docs/spring-doc-resources.zip")

gradle/ide.gradle

@@ -29,12 +29,11 @@ eclipse.classpath.file.whenMerged { classpath ->
 	classpath.entries.removeAll { entry -> (entry.path =~ /(?!.*?repack.*\.jar).*?\/([^\/]+)\/build\/libs\/[^\/]+\.jar/) }
 }
 
-
 // Use separate main/test outputs (prevents WTP from packaging test classes)
 eclipse.classpath.defaultOutputDir = file(project.name+"/bin/eclipse")
 eclipse.classpath.file.beforeMerged { classpath ->
 	classpath.entries.findAll{ it instanceof SourceFolder }.each {
-		if(it.output.startsWith("bin/")) {
+		if (it.output.startsWith("bin/")) {
 			it.output = null
 		}
 	}
@@ -56,6 +55,23 @@ eclipse.classpath.file.whenMerged { classpath ->
 	}
 }
 
+// Ensure that test fixture dependencies are handled properly in Gradle 6.7.
+// Bug fixed in Gradle 6.8: https://github.com/gradle/gradle/issues/14932 
+eclipse.classpath.file.whenMerged {
+	entries.findAll { it instanceof ProjectDependency }.each {
+		it.entryAttributes.remove('without_test_code')
+	}
+}
+
+// Ensure that JMH sources and resources are treated as test classpath entries
+// so that they can see test fixtures.
+// https://github.com/melix/jmh-gradle-plugin/issues/157
+eclipse.classpath.file.whenMerged {
+	entries.findAll { it.path =~ /src\/jmh\/(java|resources)/ }.each {
+		it.entryAttributes['test'] = 'true'
+	}
+}
+
 // Allow projects to be used as WTP modules
 eclipse.project.natures "org.eclipse.wst.common.project.facet.core.nature"
 

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-6.7-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.7.1-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists

spring-aop/src/main/java/org/springframework/aop/aspectj/AbstractAspectJAdvice.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -350,17 +350,8 @@ public abstract class AbstractAspectJAdvice implements Advice, AspectJPrecedence
 		return this.discoveredThrowingType;
 	}
 
-	private boolean isVariableName(String name) {
-		char[] chars = name.toCharArray();
-		if (!Character.isJavaIdentifierStart(chars[0])) {
-			return false;
-		}
-		for (int i = 1; i < chars.length; i++) {
-			if (!Character.isJavaIdentifierPart(chars[i])) {
-				return false;
-			}
-		}
-		return true;
+	private static boolean isVariableName(String name) {
+		return AspectJProxyUtils.isVariableName(name);
 	}
 
 
@@ -640,7 +631,6 @@ public abstract class AbstractAspectJAdvice implements Advice, AspectJPrecedence
 		}
 		try {
 			ReflectionUtils.makeAccessible(this.aspectJAdviceMethod);
-			// TODO AopUtils.invokeJoinpointUsingReflection
 			return this.aspectJAdviceMethod.invoke(this.aspectInstanceFactory.getAspectInstance(), actualArgs);
 		}
 		catch (IllegalArgumentException ex) {

spring-aop/src/main/java/org/springframework/aop/aspectj/AspectJAdviceParameterNameDiscoverer.java

@@ -470,22 +470,10 @@ public class AspectJAdviceParameterNameDiscoverer implements ParameterNameDiscov
 	 */
 	@Nullable
 	private String maybeExtractVariableName(@Nullable String candidateToken) {
-		if (!StringUtils.hasLength(candidateToken)) {
-			return null;
-		}
-		if (Character.isJavaIdentifierStart(candidateToken.charAt(0)) &&
-				Character.isLowerCase(candidateToken.charAt(0))) {
-			char[] tokenChars = candidateToken.toCharArray();
-			for (char tokenChar : tokenChars) {
-				if (!Character.isJavaIdentifierPart(tokenChar)) {
-					return null;
-				}
-			}
+		if (AspectJProxyUtils.isVariableName(candidateToken)) {
 			return candidateToken;
 		}
-		else {
-			return null;
-		}
+		return null;
 	}
 
 	/**

spring-aop/src/main/java/org/springframework/aop/aspectj/AspectJProxyUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,6 +21,8 @@ import java.util.List;
 import org.springframework.aop.Advisor;
 import org.springframework.aop.PointcutAdvisor;
 import org.springframework.aop.interceptor.ExposeInvocationInterceptor;
+import org.springframework.lang.Nullable;
+import org.springframework.util.StringUtils;
 
 /**
  * Utility methods for working with AspectJ proxies.
@@ -73,4 +75,19 @@ public abstract class AspectJProxyUtils {
 						((PointcutAdvisor) advisor).getPointcut() instanceof AspectJExpressionPointcut));
 	}
 
+	static boolean isVariableName(@Nullable String name) {
+		if (!StringUtils.hasLength(name)) {
+			return false;
+		}
+		if (!Character.isJavaIdentifierStart(name.charAt(0))) {
+			return false;
+		}
+		for (int i = 1; i < name.length(); i++) {
+			if (!Character.isJavaIdentifierPart(name.charAt(i))) {
+				return false;
+			}
+		}
+		return true;
+	}
+
 }

spring-aop/src/main/java/org/springframework/aop/aspectj/annotation/ReflectiveAspectJAdvisorFactory.java

@@ -51,6 +51,7 @@ import org.springframework.core.convert.converter.Converter;
 import org.springframework.core.convert.converter.ConvertingComparator;
 import org.springframework.lang.Nullable;
 import org.springframework.util.ReflectionUtils;
+import org.springframework.util.ReflectionUtils.MethodFilter;
 import org.springframework.util.StringUtils;
 import org.springframework.util.comparator.InstanceComparator;
 
@@ -70,7 +71,11 @@ import org.springframework.util.comparator.InstanceComparator;
 @SuppressWarnings("serial")
 public class ReflectiveAspectJAdvisorFactory extends AbstractAspectJAdvisorFactory implements Serializable {
 
-	private static final Comparator<Method> METHOD_COMPARATOR;
+	// Exclude @Pointcut methods
+	private static final MethodFilter adviceMethodFilter = ReflectionUtils.USER_DECLARED_METHODS
+			.and(method -> (AnnotationUtils.getAnnotation(method, Pointcut.class) == null));
+
+	private static final Comparator<Method> adviceMethodComparator;
 
 	static {
 		// Note: although @After is ordered before @AfterReturning and @AfterThrowing,
@@ -86,7 +91,7 @@ public class ReflectiveAspectJAdvisorFactory extends AbstractAspectJAdvisorFacto
 					return (ann != null ? ann.getAnnotation() : null);
 				});
 		Comparator<Method> methodNameComparator = new ConvertingComparator<>(Method::getName);
-		METHOD_COMPARATOR = adviceKindComparator.thenComparing(methodNameComparator);
+		adviceMethodComparator = adviceKindComparator.thenComparing(methodNameComparator);
 	}
 
 
@@ -160,15 +165,10 @@ public class ReflectiveAspectJAdvisorFactory extends AbstractAspectJAdvisorFacto
 	}
 
 	private List<Method> getAdvisorMethods(Class<?> aspectClass) {
-		final List<Method> methods = new ArrayList<>();
-		ReflectionUtils.doWithMethods(aspectClass, method -> {
-			// Exclude pointcuts
-			if (AnnotationUtils.getAnnotation(method, Pointcut.class) == null) {
-				methods.add(method);
-			}
-		}, ReflectionUtils.USER_DECLARED_METHODS);
+		List<Method> methods = new ArrayList<>();
+		ReflectionUtils.doWithMethods(aspectClass, methods::add, adviceMethodFilter);
 		if (methods.size() > 1) {
-			methods.sort(METHOD_COMPARATOR);
+			methods.sort(adviceMethodComparator);
 		}
 		return methods;
 	}

spring-aop/src/main/java/org/springframework/aop/framework/CglibAopProxy.java

@@ -48,6 +48,7 @@ import org.springframework.cglib.proxy.Factory;
 import org.springframework.cglib.proxy.MethodInterceptor;
 import org.springframework.cglib.proxy.MethodProxy;
 import org.springframework.cglib.proxy.NoOp;
+import org.springframework.core.KotlinDetector;
 import org.springframework.core.SmartClassLoader;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -752,10 +753,17 @@ class CglibAopProxy implements AopProxy, Serializable {
 				throw ex;
 			}
 			catch (Exception ex) {
-				if (ReflectionUtils.declaresException(getMethod(), ex.getClass())) {
+				if (ReflectionUtils.declaresException(getMethod(), ex.getClass()) ||
+						KotlinDetector.isKotlinType(getMethod().getDeclaringClass())) {
+					// Propagate original exception if declared on the target method
+					// (with callers expecting it). Always propagate it for Kotlin code
+					// since checked exceptions do not have to be explicitly declared there.
 					throw ex;
 				}
 				else {
+					// Checked exception thrown in the interceptor but not declared on the
+					// target method signature -> apply an UndeclaredThrowableException,
+					// aligned with standard JDK dynamic proxy behavior.
 					throw new UndeclaredThrowableException(ex);
 				}
 			}

spring-aspects/src/main/java/org/springframework/transaction/aspectj/AbstractTransactionAspect.aj

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -59,7 +59,8 @@ public abstract aspect AbstractTransactionAspect extends TransactionAspectSuppor
 
 	@Override
 	public void destroy() {
-		clearTransactionManagerCache(); // An aspect is basically a singleton
+		// An aspect is basically a singleton -> cleanup on destruction
+		clearTransactionManagerCache();
 	}
 
 	@SuppressAjWarnings("adviceDidNotMatch")

spring-beans/src/main/java/org/springframework/beans/BeanUtils.java

@@ -543,6 +543,7 @@ public abstract class BeanUtils {
 		if (targetType == null || targetType.isArray() || unknownEditorTypes.contains(targetType)) {
 			return null;
 		}
+
 		ClassLoader cl = targetType.getClassLoader();
 		if (cl == null) {
 			try {
@@ -559,28 +560,34 @@ public abstract class BeanUtils {
 				return null;
 			}
 		}
+
 		String targetTypeName = targetType.getName();
 		String editorName = targetTypeName + "Editor";
 		try {
 			Class<?> editorClass = cl.loadClass(editorName);
-			if (!PropertyEditor.class.isAssignableFrom(editorClass)) {
-				if (logger.isInfoEnabled()) {
-					logger.info("Editor class [" + editorName +
-							"] does not implement [java.beans.PropertyEditor] interface");
+			if (editorClass != null) {
+				if (!PropertyEditor.class.isAssignableFrom(editorClass)) {
+					if (logger.isInfoEnabled()) {
+						logger.info("Editor class [" + editorName +
+								"] does not implement [java.beans.PropertyEditor] interface");
+					}
+					unknownEditorTypes.add(targetType);
+					return null;
 				}
-				unknownEditorTypes.add(targetType);
-				return null;
+				return (PropertyEditor) instantiateClass(editorClass);
 			}
-			return (PropertyEditor) instantiateClass(editorClass);
+			// Misbehaving ClassLoader returned null instead of ClassNotFoundException
+			// - fall back to unknown editor type registration below
 		}
 		catch (ClassNotFoundException ex) {
-			if (logger.isTraceEnabled()) {
-				logger.trace("No property editor [" + editorName + "] found for type " +
-						targetTypeName + " according to 'Editor' suffix convention");
-			}
-			unknownEditorTypes.add(targetType);
-			return null;
+			// Ignore - fall back to unknown editor type registration below
 		}
+		if (logger.isTraceEnabled()) {
+			logger.trace("No property editor [" + editorName + "] found for type " +
+					targetTypeName + " according to 'Editor' suffix convention");
+		}
+		unknownEditorTypes.add(targetType);
+		return null;
 	}
 
 	/**

spring-beans/src/main/java/org/springframework/beans/factory/annotation/InjectionMetadata.java

@@ -141,8 +141,7 @@ public class InjectionMetadata {
 	 * Return an {@code InjectionMetadata} instance, possibly for empty elements.
 	 * @param elements the elements to inject (possibly empty)
 	 * @param clazz the target class
-	 * @return a new {@link #InjectionMetadata(Class, Collection)} instance,
-	 * or {@link #EMPTY} in case of no elements
+	 * @return a new {@link #InjectionMetadata(Class, Collection)} instance
 	 * @since 5.2
 	 */
 	public static InjectionMetadata forElements(Collection<InjectedElement> elements, Class<?> clazz) {

spring-beans/src/main/java/org/springframework/beans/factory/support/AbstractBeanFactory.java

@@ -250,7 +250,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 			throws BeansException {
 
 		String beanName = transformedBeanName(name);
-		Object bean;
+		Object beanInstance;
 
 		// Eagerly check singleton cache for manually registered singletons.
 		Object sharedInstance = getSingleton(beanName);
@@ -264,7 +264,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 					logger.trace("Returning cached instance of singleton bean '" + beanName + "'");
 				}
 			}
-			bean = getObjectForBeanInstance(sharedInstance, name, beanName, null);
+			beanInstance = getObjectForBeanInstance(sharedInstance, name, beanName, null);
 		}
 
 		else {
@@ -342,7 +342,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 							throw ex;
 						}
 					});
-					bean = getObjectForBeanInstance(sharedInstance, name, beanName, mbd);
+					beanInstance = getObjectForBeanInstance(sharedInstance, name, beanName, mbd);
 				}
 
 				else if (mbd.isPrototype()) {
@@ -355,7 +355,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 					finally {
 						afterPrototypeCreation(beanName);
 					}
-					bean = getObjectForBeanInstance(prototypeInstance, name, beanName, mbd);
+					beanInstance = getObjectForBeanInstance(prototypeInstance, name, beanName, mbd);
 				}
 
 				else {
@@ -377,7 +377,7 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 								afterPrototypeCreation(beanName);
 							}
 						});
-						bean = getObjectForBeanInstance(scopedInstance, name, beanName, mbd);
+						beanInstance = getObjectForBeanInstance(scopedInstance, name, beanName, mbd);
 					}
 					catch (IllegalStateException ex) {
 						throw new ScopeNotActiveException(beanName, scopeName, ex);
@@ -395,14 +395,19 @@ public abstract class AbstractBeanFactory extends FactoryBeanRegistrySupport imp
 			}
 		}
 
+		return adaptBeanInstance(name, beanInstance, requiredType);
+	}
+
+	@SuppressWarnings("unchecked")
+	<T> T adaptBeanInstance(String name, Object bean, @Nullable Class<?> requiredType) {
 		// Check if required type matches the type of the actual bean instance.
 		if (requiredType != null && !requiredType.isInstance(bean)) {
 			try {
-				T convertedBean = getTypeConverter().convertIfNecessary(bean, requiredType);
+				Object convertedBean = getTypeConverter().convertIfNecessary(bean, requiredType);
 				if (convertedBean == null) {
 					throw new BeanNotOfRequiredTypeException(name, requiredType, bean.getClass());
 				}
-				return convertedBean;
+				return (T) convertedBean;
 			}
 			catch (TypeMismatchException ex) {
 				if (logger.isTraceEnabled()) {

spring-beans/src/main/java/org/springframework/beans/factory/support/ConstructorResolver.java

@@ -67,6 +67,7 @@ import org.springframework.util.StringUtils;
 
 /**
  * Delegate for resolving constructors and factory methods.
+ *
  * <p>Performs constructor resolution through argument matching.
  *
  * @author Juergen Hoeller
@@ -85,7 +86,7 @@ class ConstructorResolver {
 	private static final Object[] EMPTY_ARGS = new Object[0];
 
 	/**
-	 * Marker for autowired arguments in a cached argument array, to be later replaced
+	 * Marker for autowired arguments in a cached argument array, to be replaced
 	 * by a {@linkplain #resolveAutowiredArgument resolved autowired argument}.
 	 */
 	private static final Object autowiredArgumentMarker = new Object();
@@ -149,7 +150,7 @@ class ConstructorResolver {
 				}
 			}
 			if (argsToResolve != null) {
-				argsToUse = resolvePreparedArguments(beanName, mbd, bw, constructorToUse, argsToResolve, true);
+				argsToUse = resolvePreparedArguments(beanName, mbd, bw, constructorToUse, argsToResolve);
 			}
 		}
 
@@ -410,6 +411,7 @@ class ConstructorResolver {
 			if (mbd.isSingleton() && this.beanFactory.containsSingleton(beanName)) {
 				throw new ImplicitlyAppearedSingletonException();
 			}
+			this.beanFactory.registerDependentBean(factoryBeanName, beanName);
 			factoryClass = factoryBean.getClass();
 			isStatic = false;
 		}
@@ -444,7 +446,7 @@ class ConstructorResolver {
 				}
 			}
 			if (argsToResolve != null) {
-				argsToUse = resolvePreparedArguments(beanName, mbd, bw, factoryMethodToUse, argsToResolve, true);
+				argsToUse = resolvePreparedArguments(beanName, mbd, bw, factoryMethodToUse, argsToResolve);
 			}
 		}
 
@@ -816,7 +818,7 @@ class ConstructorResolver {
 	 * Resolve the prepared arguments stored in the given bean definition.
 	 */
 	private Object[] resolvePreparedArguments(String beanName, RootBeanDefinition mbd, BeanWrapper bw,
-			Executable executable, Object[] argsToResolve, boolean fallback) {
+			Executable executable, Object[] argsToResolve) {
 
 		TypeConverter customConverter = this.beanFactory.getCustomTypeConverter();
 		TypeConverter converter = (customConverter != null ? customConverter : bw);
@@ -829,7 +831,7 @@ class ConstructorResolver {
 			Object argValue = argsToResolve[argIndex];
 			MethodParameter methodParam = MethodParameter.forExecutable(executable, argIndex);
 			if (argValue == autowiredArgumentMarker) {
-				argValue = resolveAutowiredArgument(methodParam, beanName, null, converter, fallback);
+				argValue = resolveAutowiredArgument(methodParam, beanName, null, converter, true);
 			}
 			else if (argValue instanceof BeanMetadataElement) {
 				argValue = valueResolver.resolveValueIfNecessary("constructor argument", argValue);

spring-beans/src/main/java/org/springframework/beans/factory/support/DefaultListableBeanFactory.java

@@ -1231,8 +1231,7 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 		}
 
 		if (candidateNames.length == 1) {
-			String beanName = candidateNames[0];
-			return new NamedBeanHolder<>(beanName, (T) getBean(beanName, requiredType.toClass(), args));
+			return resolveNamedBean(candidateNames[0], requiredType, args);
 		}
 		else if (candidateNames.length > 1) {
 			Map<String, Object> candidates = CollectionUtils.newLinkedHashMap(candidateNames.length);
@@ -1251,8 +1250,11 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 			}
 			if (candidateName != null) {
 				Object beanInstance = candidates.get(candidateName);
-				if (beanInstance == null || beanInstance instanceof Class) {
-					beanInstance = getBean(candidateName, requiredType.toClass(), args);
+				if (beanInstance == null) {
+					return null;
+				}
+				if (beanInstance instanceof Class) {
+					return resolveNamedBean(candidateName, requiredType, args);
 				}
 				return new NamedBeanHolder<>(candidateName, (T) beanInstance);
 			}
@@ -1264,6 +1266,17 @@ public class DefaultListableBeanFactory extends AbstractAutowireCapableBeanFacto
 		return null;
 	}
 
+	@Nullable
+	private <T> NamedBeanHolder<T> resolveNamedBean(
+			String beanName, ResolvableType requiredType, @Nullable Object[] args) throws BeansException {
+
+		Object bean = getBean(beanName, null, args);
+		if (bean instanceof NullBean) {
+			return null;
+		}
+		return new NamedBeanHolder<T>(beanName, adaptBeanInstance(beanName, bean, requiredType.toClass()));
+	}
+
 	@Override
 	@Nullable
 	public Object resolveDependency(DependencyDescriptor descriptor, @Nullable String requestingBeanName,

spring-beans/src/test/java/org/springframework/beans/factory/BeanFactoryUtilsTests.java

@@ -63,9 +63,8 @@ public class BeanFactoryUtilsTests {
 
 
 	@BeforeEach
-	public void setUp() {
+	public void setup() {
 		// Interesting hierarchical factory to test counts.
-		// Slow to read so we cache it.
 
 		DefaultListableBeanFactory grandParent = new DefaultListableBeanFactory();
 		new XmlBeanDefinitionReader(grandParent).loadBeanDefinitions(ROOT_CONTEXT);
@@ -93,7 +92,7 @@ public class BeanFactoryUtilsTests {
 	 * Check that override doesn't count as two separate beans.
 	 */
 	@Test
-	public void testHierarchicalCountBeansWithOverride() throws Exception {
+	public void testHierarchicalCountBeansWithOverride() {
 		// Leaf count
 		assertThat(this.listableBeanFactory.getBeanDefinitionCount() == 1).isTrue();
 		// Count minus duplicate
@@ -101,14 +100,14 @@ public class BeanFactoryUtilsTests {
 	}
 
 	@Test
-	public void testHierarchicalNamesWithNoMatch() throws Exception {
+	public void testHierarchicalNamesWithNoMatch() {
 		List<String> names = Arrays.asList(
 				BeanFactoryUtils.beanNamesForTypeIncludingAncestors(this.listableBeanFactory, NoOp.class));
 		assertThat(names.size()).isEqualTo(0);
 	}
 
 	@Test
-	public void testHierarchicalNamesWithMatchOnlyInRoot() throws Exception {
+	public void testHierarchicalNamesWithMatchOnlyInRoot() {
 		List<String> names = Arrays.asList(
 				BeanFactoryUtils.beanNamesForTypeIncludingAncestors(this.listableBeanFactory, IndexedTestBean.class));
 		assertThat(names.size()).isEqualTo(1);
@@ -118,7 +117,7 @@ public class BeanFactoryUtilsTests {
 	}
 
 	@Test
-	public void testGetBeanNamesForTypeWithOverride() throws Exception {
+	public void testGetBeanNamesForTypeWithOverride() {
 		List<String> names = Arrays.asList(
 				BeanFactoryUtils.beanNamesForTypeIncludingAncestors(this.listableBeanFactory, ITestBean.class));
 		// includes 2 TestBeans from FactoryBeans (DummyFactory definitions)
@@ -236,7 +235,7 @@ public class BeanFactoryUtilsTests {
 	}
 
 	@Test
-	public void testHierarchicalResolutionWithOverride() throws Exception {
+	public void testHierarchicalResolutionWithOverride() {
 		Object test3 = this.listableBeanFactory.getBean("test3");
 		Object test = this.listableBeanFactory.getBean("test");
 
@@ -276,14 +275,14 @@ public class BeanFactoryUtilsTests {
 	}
 
 	@Test
-	public void testHierarchicalNamesForAnnotationWithNoMatch() throws Exception {
+	public void testHierarchicalNamesForAnnotationWithNoMatch() {
 		List<String> names = Arrays.asList(
 				BeanFactoryUtils.beanNamesForAnnotationIncludingAncestors(this.listableBeanFactory, Override.class));
 		assertThat(names.size()).isEqualTo(0);
 	}
 
 	@Test
-	public void testHierarchicalNamesForAnnotationWithMatchOnlyInRoot() throws Exception {
+	public void testHierarchicalNamesForAnnotationWithMatchOnlyInRoot() {
 		List<String> names = Arrays.asList(
 				BeanFactoryUtils.beanNamesForAnnotationIncludingAncestors(this.listableBeanFactory, TestAnnotation.class));
 		assertThat(names.size()).isEqualTo(1);
@@ -293,7 +292,7 @@ public class BeanFactoryUtilsTests {
 	}
 
 	@Test
-	public void testGetBeanNamesForAnnotationWithOverride() throws Exception {
+	public void testGetBeanNamesForAnnotationWithOverride() {
 		AnnotatedBean annotatedBean = new AnnotatedBean();
 		this.listableBeanFactory.registerSingleton("anotherAnnotatedBean", annotatedBean);
 		List<String> names = Arrays.asList(
@@ -433,6 +432,7 @@ public class BeanFactoryUtilsTests {
 		String basePackage() default "";
 	}
 
+
 	@Retention(RetentionPolicy.RUNTIME)
 	@ControllerAdvice
 	@interface RestControllerAdvice {
@@ -444,18 +444,23 @@ public class BeanFactoryUtilsTests {
 		String basePackage() default "";
 	}
 
+
 	@ControllerAdvice("com.example")
 	static class ControllerAdviceClass {
 	}
 
+
 	@RestControllerAdvice("com.example")
 	static class RestControllerAdviceClass {
 	}
 
+
 	static class TestBeanSmartFactoryBean implements SmartFactoryBean<TestBean> {
 
 		private final TestBean testBean = new TestBean("enigma", 42);
+
 		private final boolean singleton;
+
 		private final boolean prototype;
 
 		TestBeanSmartFactoryBean(boolean singleton, boolean prototype) {
@@ -478,7 +483,7 @@ public class BeanFactoryUtilsTests {
 			return TestBean.class;
 		}
 
-		public TestBean getObject() throws Exception {
+		public TestBean getObject() {
 			// We don't really care if the actual instance is a singleton or prototype
 			// for the tests that use this factory.
 			return this.testBean;

spring-beans/src/test/java/org/springframework/beans/factory/DefaultListableBeanFactoryTests.java

@@ -785,12 +785,13 @@ class DefaultListableBeanFactoryTests {
 		factory.registerBeanDefinition("child", childDefinition);
 		factory.registerAlias("parent", "alias");
 
-		TestBean child = (TestBean) factory.getBean("child");
+		TestBean child = factory.getBean("child", TestBean.class);
 		assertThat(child.getName()).isEqualTo(EXPECTED_NAME);
 		assertThat(child.getAge()).isEqualTo(EXPECTED_AGE);
-		Object mergedBeanDefinition2 = factory.getMergedBeanDefinition("child");
+		BeanDefinition mergedBeanDefinition1 = factory.getMergedBeanDefinition("child");
+		BeanDefinition mergedBeanDefinition2 = factory.getMergedBeanDefinition("child");
 
-		assertThat(mergedBeanDefinition2).as("Use cached merged bean definition").isEqualTo(mergedBeanDefinition2);
+		assertThat(mergedBeanDefinition1).as("Use cached merged bean definition").isSameAs(mergedBeanDefinition2);
 	}
 
 	@Test
@@ -1838,8 +1839,7 @@ class DefaultListableBeanFactoryTests {
 		assertThat(factoryBean).as("The FactoryBean should have been registered.").isNotNull();
 		FactoryBeanDependentBean bean = (FactoryBeanDependentBean) lbf.autowire(FactoryBeanDependentBean.class,
 				AutowireCapableBeanFactory.AUTOWIRE_BY_TYPE, true);
-		Object mergedBeanDefinition2 = bean.getFactoryBean();
-		assertThat(mergedBeanDefinition2).as("The FactoryBeanDependentBean should have been autowired 'by type' with the LazyInitFactory.").isEqualTo(mergedBeanDefinition2);
+		assertThat(bean.getFactoryBean()).as("The FactoryBeanDependentBean should have been autowired 'by type' with the LazyInitFactory.").isEqualTo(factoryBean);
 	}
 
 	@Test
@@ -2388,8 +2388,7 @@ class DefaultListableBeanFactoryTests {
 		BeanWithDestroyMethod.closeCount = 0;
 		lbf.preInstantiateSingletons();
 		lbf.destroySingletons();
-		Object mergedBeanDefinition2 = BeanWithDestroyMethod.closeCount;
-		assertThat(mergedBeanDefinition2).as("Destroy methods invoked").isEqualTo(mergedBeanDefinition2);
+		assertThat(BeanWithDestroyMethod.closeCount).as("Destroy methods invoked").isEqualTo(1);
 	}
 
 	@Test
@@ -2403,8 +2402,7 @@ class DefaultListableBeanFactoryTests {
 		BeanWithDestroyMethod.closeCount = 0;
 		lbf.preInstantiateSingletons();
 		lbf.destroySingletons();
-		Object mergedBeanDefinition2 = BeanWithDestroyMethod.closeCount;
-		assertThat(mergedBeanDefinition2).as("Destroy methods invoked").isEqualTo(mergedBeanDefinition2);
+		assertThat(BeanWithDestroyMethod.closeCount).as("Destroy methods invoked").isEqualTo(2);
 	}
 
 	@Test
@@ -2419,8 +2417,7 @@ class DefaultListableBeanFactoryTests {
 		BeanWithDestroyMethod.closeCount = 0;
 		lbf.preInstantiateSingletons();
 		lbf.destroySingletons();
-		Object mergedBeanDefinition2 = BeanWithDestroyMethod.closeCount;
-		assertThat(mergedBeanDefinition2).as("Destroy methods invoked").isEqualTo(mergedBeanDefinition2);
+		assertThat(BeanWithDestroyMethod.closeCount).as("Destroy methods invoked").isEqualTo(1);
 	}
 
 	@Test
@@ -2542,14 +2539,15 @@ class DefaultListableBeanFactoryTests {
 		factory.registerBeanDefinition("child", child);
 
 		AbstractBeanDefinition def = (AbstractBeanDefinition) factory.getBeanDefinition("child");
-		Object mergedBeanDefinition2 = def.getScope();
-		assertThat(mergedBeanDefinition2).as("Child 'scope' not overriding parent scope (it must).").isEqualTo(mergedBeanDefinition2);
+		assertThat(def.getScope()).as("Child 'scope' not overriding parent scope (it must).").isEqualTo(theChildScope);
 	}
 
 	@Test
 	void scopeInheritanceForChildBeanDefinitions() {
+		String theParentScope = "bonanza!";
+
 		RootBeanDefinition parent = new RootBeanDefinition();
-		parent.setScope("bonanza!");
+		parent.setScope(theParentScope);
 
 		AbstractBeanDefinition child = new ChildBeanDefinition("parent");
 		child.setBeanClass(TestBean.class);
@@ -2559,8 +2557,7 @@ class DefaultListableBeanFactoryTests {
 		factory.registerBeanDefinition("child", child);
 
 		BeanDefinition def = factory.getMergedBeanDefinition("child");
-		Object mergedBeanDefinition2 = def.getScope();
-		assertThat(mergedBeanDefinition2).as("Child 'scope' not inherited").isEqualTo(mergedBeanDefinition2);
+		assertThat(def.getScope()).as("Child 'scope' not inherited").isEqualTo(theParentScope);
 	}
 
 	@Test
@@ -2596,15 +2593,12 @@ class DefaultListableBeanFactoryTests {
 		});
 		lbf.preInstantiateSingletons();
 		TestBean tb = (TestBean) lbf.getBean("test");
-		Object mergedBeanDefinition2 = tb.getName();
-		assertThat(mergedBeanDefinition2).as("Name was set on field by IAPP").isEqualTo(mergedBeanDefinition2);
+		assertThat(tb.getName()).as("Name was set on field by IAPP").isEqualTo(nameSetOnField);
 		if (!skipPropertyPopulation) {
-			Object mergedBeanDefinition21 = tb.getAge();
-			assertThat(mergedBeanDefinition21).as("Property value still set").isEqualTo(mergedBeanDefinition21);
+			assertThat(tb.getAge()).as("Property value still set").isEqualTo(ageSetByPropertyValue);
 		}
 		else {
-			Object mergedBeanDefinition21 = tb.getAge();
-			assertThat(mergedBeanDefinition21).as("Property value was NOT set and still has default value").isEqualTo(mergedBeanDefinition21);
+			assertThat(tb.getAge()).as("Property value was NOT set and still has default value").isEqualTo(0);
 		}
 	}
 

spring-context/src/main/java/org/springframework/context/PayloadApplicationEvent.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,8 @@
 
 package org.springframework.context;
 
+import java.util.function.Consumer;
+
 import org.springframework.core.ResolvableType;
 import org.springframework.core.ResolvableTypeProvider;
 import org.springframework.util.Assert;
@@ -23,11 +25,12 @@ import org.springframework.util.Assert;
 /**
  * An {@link ApplicationEvent} that carries an arbitrary payload.
  *
- * <p>Mainly intended for internal use within the framework.
- *
  * @author Stephane Nicoll
+ * @author Juergen Hoeller
  * @since 4.2
  * @param <T> the payload type of the event
+ * @see ApplicationEventPublisher#publishEvent(Object)
+ * @see ApplicationListener#forPayload(Consumer)
  */
 @SuppressWarnings("serial")
 public class PayloadApplicationEvent<T> extends ApplicationEvent implements ResolvableTypeProvider {

spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassPostProcessor.java

@@ -427,15 +427,11 @@ public class ConfigurationClassPostProcessor implements BeanDefinitionRegistryPo
 				configBeanDefs.put(beanName, (AbstractBeanDefinition) beanDef);
 			}
 		}
-		if (configBeanDefs.isEmpty()) {
+		if (configBeanDefs.isEmpty() || IN_NATIVE_IMAGE) {
 			// nothing to enhance -> return immediately
 			enhanceConfigClasses.end();
 			return;
 		}
-		if (IN_NATIVE_IMAGE) {
-			throw new BeanDefinitionStoreException("@Configuration classes need to be marked as " +
-					"proxyBeanMethods=false. Found: " + configBeanDefs.keySet());
-		}
 
 		ConfigurationClassEnhancer enhancer = new ConfigurationClassEnhancer();
 		for (Map.Entry<String, AbstractBeanDefinition> entry : configBeanDefs.entrySet()) {

spring-context/src/main/java/org/springframework/context/event/SimpleApplicationEventMulticaster.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -24,9 +24,8 @@ import org.apache.commons.logging.LogFactory;
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.context.ApplicationEvent;
 import org.springframework.context.ApplicationListener;
+import org.springframework.context.PayloadApplicationEvent;
 import org.springframework.core.ResolvableType;
-import org.springframework.core.metrics.ApplicationStartup;
-import org.springframework.core.metrics.StartupStep;
 import org.springframework.lang.Nullable;
 import org.springframework.util.ErrorHandler;
 
@@ -58,7 +57,7 @@ public class SimpleApplicationEventMulticaster extends AbstractApplicationEventM
 	private ErrorHandler errorHandler;
 
 	@Nullable
-	private ApplicationStartup applicationStartup;
+	private volatile Log lazyLogger;
 
 
 	/**
@@ -127,22 +126,6 @@ public class SimpleApplicationEventMulticaster extends AbstractApplicationEventM
 		return this.errorHandler;
 	}
 
-	/**
-	 * Set the {@link ApplicationStartup} to track event listener invocations during startup.
-	 * @since 5.3
-	 */
-	public void setApplicationStartup(@Nullable ApplicationStartup applicationStartup) {
-		this.applicationStartup = applicationStartup;
-	}
-
-	/**
-	 * Return the current application startup for this multicaster.
-	 */
-	@Nullable
-	public ApplicationStartup getApplicationStartup() {
-		return this.applicationStartup;
-	}
-
 	@Override
 	public void multicastEvent(ApplicationEvent event) {
 		multicastEvent(event, resolveDefaultEventType(event));
@@ -156,16 +139,6 @@ public class SimpleApplicationEventMulticaster extends AbstractApplicationEventM
 			if (executor != null) {
 				executor.execute(() -> invokeListener(listener, event));
 			}
-			else if (this.applicationStartup != null) {
-				StartupStep invocationStep = this.applicationStartup.start("spring.event.invoke-listener");
-				invokeListener(listener, event);
-				invocationStep.tag("event", event::toString);
-				if (eventType != null) {
-					invocationStep.tag("eventType", eventType::toString);
-				}
-				invocationStep.tag("listener", listener::toString);
-				invocationStep.end();
-			}
 			else {
 				invokeListener(listener, event);
 			}
@@ -204,12 +177,18 @@ public class SimpleApplicationEventMulticaster extends AbstractApplicationEventM
 		}
 		catch (ClassCastException ex) {
 			String msg = ex.getMessage();
-			if (msg == null || matchesClassCastMessage(msg, event.getClass())) {
+			if (msg == null || matchesClassCastMessage(msg, event.getClass()) ||
+					(event instanceof PayloadApplicationEvent &&
+							matchesClassCastMessage(msg, ((PayloadApplicationEvent) event).getPayload().getClass()))) {
 				// Possibly a lambda-defined listener which we could not resolve the generic event type for
-				// -> let's suppress the exception and just log a debug message.
-				Log logger = LogFactory.getLog(getClass());
-				if (logger.isTraceEnabled()) {
-					logger.trace("Non-matching event type for listener: " + listener, ex);
+				// -> let's suppress the exception.
+				Log loggerToUse = this.lazyLogger;
+				if (loggerToUse == null) {
+					loggerToUse = LogFactory.getLog(getClass());
+					this.lazyLogger = loggerToUse;
+				}
+				if (loggerToUse.isTraceEnabled()) {
+					loggerToUse.trace("Non-matching event type for listener: " + listener, ex);
 				}
 			}
 			else {

spring-context/src/main/java/org/springframework/context/support/AbstractApplicationContext.java

@@ -815,9 +815,7 @@ public abstract class AbstractApplicationContext extends DefaultResourceLoader
 			}
 		}
 		else {
-			SimpleApplicationEventMulticaster simpleApplicationEventMulticaster = new SimpleApplicationEventMulticaster(beanFactory);
-			simpleApplicationEventMulticaster.setApplicationStartup(getApplicationStartup());
-			this.applicationEventMulticaster = simpleApplicationEventMulticaster;
+			this.applicationEventMulticaster = new SimpleApplicationEventMulticaster(beanFactory);
 			beanFactory.registerSingleton(APPLICATION_EVENT_MULTICASTER_BEAN_NAME, this.applicationEventMulticaster);
 			if (logger.isTraceEnabled()) {
 				logger.trace("No '" + APPLICATION_EVENT_MULTICASTER_BEAN_NAME + "' bean, using " +

spring-context/src/main/java/org/springframework/format/annotation/DateTimeFormat.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -106,7 +106,6 @@ public @interface DateTimeFormat {
 		/**
 		 * The most common ISO DateTime Format {@code yyyy-MM-dd'T'HH:mm:ss.SSSXXX},
 		 * e.g. "2000-10-31T01:30:00.000-05:00".
-		 * <p>This is the default if no annotation value is specified.
 		 */
 		DATE_TIME,
 

spring-context/src/main/java/org/springframework/scheduling/support/BitsCronField.java

@@ -19,14 +19,13 @@ package org.springframework.scheduling.support;
 import java.time.DateTimeException;
 import java.time.temporal.Temporal;
 import java.time.temporal.ValueRange;
-import java.util.BitSet;
 
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
 /**
- * Efficient {@link BitSet}-based extension of {@link CronField}.
+ * Efficient bitwise-operator extension of {@link CronField}.
  * Created using the {@code parse*} methods.
  *
  * @author Arjen Poutsma
@@ -130,8 +129,8 @@ final class BitsCronField extends CronField {
 					result.setBits(range);
 				}
 				else {
-					String rangeStr = value.substring(0, slashPos);
-					String deltaStr = value.substring(slashPos + 1);
+					String rangeStr = field.substring(0, slashPos);
+					String deltaStr = field.substring(slashPos + 1);
 					ValueRange range = parseRange(rangeStr, type);
 					if (rangeStr.indexOf('-') == -1) {
 						range = ValueRange.of(range.getMinimum(), type.range().getMaximum());

spring-context/src/main/java/org/springframework/scheduling/support/CompositeCronField.java

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2002-2021 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.scheduling.support;
+
+import java.time.temporal.Temporal;
+
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+
+/**
+ * Extension of {@link CronField} that wraps an array of cron fields.
+ *
+ * @author Arjen Poutsma
+ * @since 5.3.3
+ */
+final class CompositeCronField extends CronField {
+
+	private final CronField[] fields;
+
+	private final String value;
+
+
+	private CompositeCronField(Type type, CronField[] fields, String value) {
+		super(type);
+		this.fields = fields;
+		this.value = value;
+	}
+
+	/**
+	 * Composes the given fields into a {@link CronField}.
+	 */
+	public static CronField compose(CronField[] fields, Type type, String value) {
+		Assert.notEmpty(fields, "Fields must not be empty");
+		Assert.hasLength(value, "Value must not be empty");
+
+		if (fields.length == 1) {
+			return fields[0];
+		}
+		else {
+			return new CompositeCronField(type, fields, value);
+		}
+	}
+
+
+	@Nullable
+	@Override
+	public <T extends Temporal & Comparable<? super T>> T nextOrSame(T temporal) {
+		T result = null;
+		for (CronField field : this.fields) {
+			T candidate = field.nextOrSame(temporal);
+			if (result == null ||
+					candidate != null && candidate.compareTo(result) < 0) {
+				result = candidate;
+			}
+		}
+		return result;
+	}
+
+
+	@Override
+	public int hashCode() {
+		return this.value.hashCode();
+	}
+
+	@Override
+	public boolean equals(Object o) {
+		if (this == o) {
+			return true;
+		}
+		if (!(o instanceof CompositeCronField)) {
+			return false;
+		}
+		CompositeCronField other = (CompositeCronField) o;
+		return type() == other.type() &&
+				this.value.equals(other.value);
+	}
+
+	@Override
+	public String toString() {
+		return type() + " '" + this.value + "'";
+
+	}
+}

spring-context/src/main/java/org/springframework/scheduling/support/CronField.java

@@ -20,8 +20,10 @@ import java.time.DateTimeException;
 import java.time.temporal.ChronoField;
 import java.time.temporal.Temporal;
 import java.time.temporal.ValueRange;
+import java.util.function.BiFunction;
 
 import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
 import org.springframework.util.StringUtils;
 
 /**
@@ -77,11 +79,18 @@ abstract class CronField {
 	 * Parse the given value into a days of months {@code CronField}, the fourth entry of a cron expression.
 	 */
 	public static CronField parseDaysOfMonth(String value) {
-		if (value.contains("L") || value.contains("W")) {
-			return QuartzCronField.parseDaysOfMonth(value);
+		if (!QuartzCronField.isQuartzDaysOfMonthField(value)) {
+			return BitsCronField.parseDaysOfMonth(value);
 		}
 		else {
-			return BitsCronField.parseDaysOfMonth(value);
+			return parseList(value, Type.DAY_OF_MONTH, (field, type) -> {
+				if (QuartzCronField.isQuartzDaysOfMonthField(field)) {
+					return QuartzCronField.parseDaysOfMonth(field);
+				}
+				else {
+					return BitsCronField.parseDaysOfMonth(field);
+				}
+			});
 		}
 	}
 
@@ -98,15 +107,32 @@ abstract class CronField {
 	 */
 	public static CronField parseDaysOfWeek(String value) {
 		value = replaceOrdinals(value, DAYS);
-		if (value.contains("L") || value.contains("#")) {
-			return QuartzCronField.parseDaysOfWeek(value);
+		if (!QuartzCronField.isQuartzDaysOfWeekField(value)) {
+			return BitsCronField.parseDaysOfWeek(value);
 		}
 		else {
-			return BitsCronField.parseDaysOfWeek(value);
+			return parseList(value, Type.DAY_OF_WEEK, (field, type) -> {
+				if (QuartzCronField.isQuartzDaysOfWeekField(field)) {
+					return QuartzCronField.parseDaysOfWeek(field);
+				}
+				else {
+					return BitsCronField.parseDaysOfWeek(field);
+				}
+			});
 		}
 	}
 
 
+	private static CronField parseList(String value, Type type, BiFunction<String, Type, CronField> parseFieldFunction) {
+		Assert.hasLength(value, "Value must not be empty");
+		String[] fields = StringUtils.delimitedListToStringArray(value, ",");
+		CronField[] cronFields = new CronField[fields.length];
+		for (int i = 0; i < fields.length; i++) {
+			cronFields[i] = parseFieldFunction.apply(fields[i], type);
+		}
+		return CompositeCronField.compose(cronFields, type, value);
+	}
+
 	private static String replaceOrdinals(String value, String[] list) {
 		value = value.toUpperCase();
 		for (int i = 0; i < list.length; i++) {

spring-context/src/main/java/org/springframework/scheduling/support/QuartzCronField.java

@@ -78,6 +78,12 @@ final class QuartzCronField extends CronField {
 		this.rollForwardType = rollForwardType;
 	}
 
+	/**
+	 * Returns whether the given value is a Quartz day-of-month field.
+	 */
+	public static boolean isQuartzDaysOfMonthField(String value) {
+		return value.contains("L") || value.contains("W");
+	}
 
 	/**
 	 * Parse the given value into a days of months {@code QuartzCronField}, the fourth entry of a cron expression.
@@ -125,6 +131,13 @@ final class QuartzCronField extends CronField {
 		throw new IllegalArgumentException("No 'L' or 'W' found in '" + value + "'");
 	}
 
+	/**
+	 * Returns whether the given value is a Quartz day-of-week field.
+	 */
+	public static boolean isQuartzDaysOfWeekField(String value) {
+		return value.contains("L") || value.contains("#");
+	}
+
 	/**
 	 * Parse the given value into a days of week {@code QuartzCronField}, the sixth entry of a cron expression.
 	 * Expects a "L" or "#" in the given value.

spring-context/src/test/java/org/springframework/aop/aspectj/autoproxy/AtAspectJAfterThrowingTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,24 +36,26 @@ import static org.assertj.core.api.Assertions.assertThat;
 public class AtAspectJAfterThrowingTests {
 
 	@Test
-	public void testAccessThrowable() throws Exception {
+	public void testAccessThrowable() {
 		ClassPathXmlApplicationContext ctx =
-			new ClassPathXmlApplicationContext(getClass().getSimpleName() + "-context.xml", getClass());
+				new ClassPathXmlApplicationContext(getClass().getSimpleName() + "-context.xml", getClass());
 
 		ITestBean bean = (ITestBean) ctx.getBean("testBean");
 		ExceptionHandlingAspect aspect = (ExceptionHandlingAspect) ctx.getBean("aspect");
 
 		assertThat(AopUtils.isAopProxy(bean)).isTrue();
+		IOException exceptionThrown = null;
 		try {
 			bean.unreliableFileOperation();
 		}
-		catch (IOException e) {
-			//
+		catch (IOException ex) {
+			exceptionThrown = ex;
 		}
 
 		assertThat(aspect.handled).isEqualTo(1);
-		assertThat(aspect.lastException).isNotNull();
+		assertThat(aspect.lastException).isSameAs(exceptionThrown);
 	}
+
 }
 
 

spring-context/src/test/java/org/springframework/aop/aspectj/autoproxy/AtAspectJAnnotationBindingTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,6 +36,7 @@ import static org.assertj.core.api.Assertions.assertThat;
 public class AtAspectJAnnotationBindingTests {
 
 	private AnnotatedTestBean testBean;
+
 	private ClassPathXmlApplicationContext ctx;
 
 
@@ -70,8 +71,7 @@ public class AtAspectJAnnotationBindingTests {
 class AtAspectJAnnotationBindingTestAspect {
 
 	@Around("execution(* *(..)) && @annotation(testAnn)")
-	public Object doWithAnnotation(ProceedingJoinPoint pjp, TestAnnotation testAnn)
-	throws Throwable {
+	public Object doWithAnnotation(ProceedingJoinPoint pjp, TestAnnotation testAnn) throws Throwable {
 		String annValue = testAnn.value();
 		Object result = pjp.proceed();
 		return (result instanceof String ? annValue + " " + result : result);

spring-context/src/test/java/org/springframework/context/annotation/AnnotationConfigApplicationContextTests.java

@@ -271,9 +271,15 @@ class AnnotationConfigApplicationContextTests {
 		assertThat(ObjectUtils.containsElement(context.getBeanNamesForType(BeanA.class), "a")).isTrue();
 		assertThat(ObjectUtils.containsElement(context.getBeanNamesForType(BeanB.class), "b")).isTrue();
 		assertThat(ObjectUtils.containsElement(context.getBeanNamesForType(BeanC.class), "c")).isTrue();
+
 		assertThat(context.getBeansOfType(BeanA.class)).isEmpty();
 		assertThat(context.getBeansOfType(BeanB.class).values().iterator().next()).isSameAs(context.getBean(BeanB.class));
 		assertThat(context.getBeansOfType(BeanC.class).values().iterator().next()).isSameAs(context.getBean(BeanC.class));
+
+		assertThatExceptionOfType(NoSuchBeanDefinitionException.class).isThrownBy(() ->
+				context.getBeanFactory().resolveNamedBean(BeanA.class));
+		assertThat(context.getBeanFactory().resolveNamedBean(BeanB.class).getBeanInstance()).isSameAs(context.getBean(BeanB.class));
+		assertThat(context.getBeanFactory().resolveNamedBean(BeanC.class).getBeanInstance()).isSameAs(context.getBean(BeanC.class));
 	}
 
 	@Test

spring-context/src/test/java/org/springframework/context/annotation/ConfigurationClassPostProcessorTests.java

@@ -20,7 +20,6 @@ import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
-import java.util.Arrays;
 import java.util.List;
 import java.util.Map;
 
@@ -66,7 +65,6 @@ import org.springframework.core.task.SimpleAsyncTaskExecutor;
 import org.springframework.core.task.SyncTaskExecutor;
 import org.springframework.stereotype.Component;
 import org.springframework.util.Assert;
-import org.springframework.util.ObjectUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
@@ -77,13 +75,13 @@ import static org.assertj.core.api.Assertions.assertThatIllegalStateException;
  * @author Juergen Hoeller
  * @author Sam Brannen
  */
-public class ConfigurationClassPostProcessorTests {
+class ConfigurationClassPostProcessorTests {
 
 	private final DefaultListableBeanFactory beanFactory = new DefaultListableBeanFactory();
 
 
 	@BeforeEach
-	public void setup() {
+	void setup() {
 		QualifierAnnotationAutowireCandidateResolver acr = new QualifierAnnotationAutowireCandidateResolver();
 		acr.setBeanFactory(this.beanFactory);
 		this.beanFactory.setAutowireCandidateResolver(acr);
@@ -99,7 +97,7 @@ public class ConfigurationClassPostProcessorTests {
 	 * We test for such a case below, and in doing so prove that enhancement is working.
 	 */
 	@Test
-	public void enhancementIsPresentBecauseSingletonSemanticsAreRespected() {
+	void enhancementIsPresentBecauseSingletonSemanticsAreRespected() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(SingletonBeanConfig.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -107,11 +105,13 @@ public class ConfigurationClassPostProcessorTests {
 		Foo foo = beanFactory.getBean("foo", Foo.class);
 		Bar bar = beanFactory.getBean("bar", Bar.class);
 		assertThat(bar.foo).isSameAs(foo);
-		assertThat(Arrays.asList(beanFactory.getDependentBeans("foo")).contains("bar")).isTrue();
+		assertThat(beanFactory.getDependentBeans("foo")).contains("bar");
+		assertThat(beanFactory.getDependentBeans("config")).contains("foo");
+		assertThat(beanFactory.getDependentBeans("config")).contains("bar");
 	}
 
 	@Test
-	public void enhancementIsPresentBecauseSingletonSemanticsAreRespectedUsingAsm() {
+	void enhancementIsPresentBecauseSingletonSemanticsAreRespectedUsingAsm() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(SingletonBeanConfig.class.getName()));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -119,11 +119,13 @@ public class ConfigurationClassPostProcessorTests {
 		Foo foo = beanFactory.getBean("foo", Foo.class);
 		Bar bar = beanFactory.getBean("bar", Bar.class);
 		assertThat(bar.foo).isSameAs(foo);
-		assertThat(Arrays.asList(beanFactory.getDependentBeans("foo")).contains("bar")).isTrue();
+		assertThat(beanFactory.getDependentBeans("foo")).contains("bar");
+		assertThat(beanFactory.getDependentBeans("config")).contains("foo");
+		assertThat(beanFactory.getDependentBeans("config")).contains("bar");
 	}
 
 	@Test
-	public void enhancementIsNotPresentForProxyBeanMethodsFlagSetToFalse() {
+	void enhancementIsNotPresentForProxyBeanMethodsFlagSetToFalse() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(NonEnhancedSingletonBeanConfig.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -134,7 +136,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void enhancementIsNotPresentForProxyBeanMethodsFlagSetToFalseUsingAsm() {
+	void enhancementIsNotPresentForProxyBeanMethodsFlagSetToFalseUsingAsm() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(NonEnhancedSingletonBeanConfig.class.getName()));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -145,7 +147,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void enhancementIsNotPresentForStaticMethods() {
+	void enhancementIsNotPresentForStaticMethods() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(StaticSingletonBeanConfig.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -158,7 +160,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void enhancementIsNotPresentForStaticMethodsUsingAsm() {
+	void enhancementIsNotPresentForStaticMethodsUsingAsm() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(StaticSingletonBeanConfig.class.getName()));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -171,7 +173,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void configurationIntrospectionOfInnerClassesWorksWithDotNameSyntax() {
+	void configurationIntrospectionOfInnerClassesWorksWithDotNameSyntax() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(getClass().getName() + ".SingletonBeanConfig"));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -185,7 +187,7 @@ public class ConfigurationClassPostProcessorTests {
 	 * if a bean class is already loaded.
 	 */
 	@Test
-	public void alreadyLoadedConfigurationClasses() {
+	void alreadyLoadedConfigurationClasses() {
 		beanFactory.registerBeanDefinition("unloadedConfig", new RootBeanDefinition(UnloadedConfig.class.getName()));
 		beanFactory.registerBeanDefinition("loadedConfig", new RootBeanDefinition(LoadedConfig.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
@@ -198,7 +200,7 @@ public class ConfigurationClassPostProcessorTests {
 	 * Tests whether a bean definition without a specified bean class is handled correctly.
 	 */
 	@Test
-	public void postProcessorIntrospectsInheritedDefinitionsCorrectly() {
+	void postProcessorIntrospectsInheritedDefinitionsCorrectly() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(SingletonBeanConfig.class));
 		beanFactory.registerBeanDefinition("parent", new RootBeanDefinition(TestBean.class));
 		beanFactory.registerBeanDefinition("child", new ChildBeanDefinition("parent"));
@@ -210,96 +212,96 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedConfigurationUsingReflection() {
+	void postProcessorWorksWithComposedConfigurationUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(ComposedConfigurationClass.class);
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedConfigurationUsingAsm() {
+	void postProcessorWorksWithComposedConfigurationUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(ComposedConfigurationClass.class.getName());
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForBasePackageUsingReflection() {
+	void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForBasePackageUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ComposedConfigurationWithAttributeOverrideForBasePackage.class);
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForBasePackageUsingAsm() {
+	void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForBasePackageUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ComposedConfigurationWithAttributeOverrideForBasePackage.class.getName());
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForExcludeFilterUsingReflection() {
+	void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForExcludeFilterUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ComposedConfigurationWithAttributeOverrideForExcludeFilter.class);
 		assertSupportForComposedAnnotationWithExclude(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForExcludeFilterUsingAsm() {
+	void postProcessorWorksWithComposedConfigurationWithAttributeOverrideForExcludeFilterUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ComposedConfigurationWithAttributeOverrideForExcludeFilter.class.getName());
 		assertSupportForComposedAnnotationWithExclude(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithExtendedConfigurationWithAttributeOverrideForExcludesFilterUsingReflection() {
+	void postProcessorWorksWithExtendedConfigurationWithAttributeOverrideForExcludesFilterUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ExtendedConfigurationWithAttributeOverrideForExcludeFilter.class);
 		assertSupportForComposedAnnotationWithExclude(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithExtendedConfigurationWithAttributeOverrideForExcludesFilterUsingAsm() {
+	void postProcessorWorksWithExtendedConfigurationWithAttributeOverrideForExcludesFilterUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ExtendedConfigurationWithAttributeOverrideForExcludeFilter.class.getName());
 		assertSupportForComposedAnnotationWithExclude(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedComposedConfigurationWithAttributeOverridesUsingReflection() {
+	void postProcessorWorksWithComposedComposedConfigurationWithAttributeOverridesUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ComposedComposedConfigurationWithAttributeOverridesClass.class);
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithComposedComposedConfigurationWithAttributeOverridesUsingAsm() {
+	void postProcessorWorksWithComposedComposedConfigurationWithAttributeOverridesUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				ComposedComposedConfigurationWithAttributeOverridesClass.class.getName());
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesUsingReflection() {
+	void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				MetaComponentScanConfigurationWithAttributeOverridesClass.class);
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesUsingAsm() {
+	void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				MetaComponentScanConfigurationWithAttributeOverridesClass.class.getName());
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesSubclassUsingReflection() {
+	void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesSubclassUsingReflection() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				SubMetaComponentScanConfigurationWithAttributeOverridesClass.class);
 		assertSupportForComposedAnnotation(beanDefinition);
 	}
 
 	@Test
-	public void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesSubclassUsingAsm() {
+	void postProcessorWorksWithMetaComponentScanConfigurationWithAttributeOverridesSubclassUsingAsm() {
 		RootBeanDefinition beanDefinition = new RootBeanDefinition(
 				SubMetaComponentScanConfigurationWithAttributeOverridesClass.class.getName());
 		assertSupportForComposedAnnotation(beanDefinition);
@@ -324,7 +326,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void postProcessorOverridesNonApplicationBeanDefinitions() {
+	void postProcessorOverridesNonApplicationBeanDefinitions() {
 		RootBeanDefinition rbd = new RootBeanDefinition(TestBean.class);
 		rbd.setRole(RootBeanDefinition.ROLE_SUPPORT);
 		beanFactory.registerBeanDefinition("bar", rbd);
@@ -337,7 +339,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void postProcessorDoesNotOverrideRegularBeanDefinitions() {
+	void postProcessorDoesNotOverrideRegularBeanDefinitions() {
 		RootBeanDefinition rbd = new RootBeanDefinition(TestBean.class);
 		rbd.setResource(new DescriptiveResource("XML or something"));
 		beanFactory.registerBeanDefinition("bar", rbd);
@@ -349,7 +351,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void postProcessorDoesNotOverrideRegularBeanDefinitionsEvenWithScopedProxy() {
+	void postProcessorDoesNotOverrideRegularBeanDefinitionsEvenWithScopedProxy() {
 		RootBeanDefinition rbd = new RootBeanDefinition(TestBean.class);
 		rbd.setResource(new DescriptiveResource("XML or something"));
 		BeanDefinitionHolder proxied = ScopedProxyUtils.createScopedProxy(
@@ -363,7 +365,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void postProcessorFailsOnImplicitOverrideIfOverridingIsNotAllowed() {
+	void postProcessorFailsOnImplicitOverrideIfOverridingIsNotAllowed() {
 		RootBeanDefinition rbd = new RootBeanDefinition(TestBean.class);
 		rbd.setResource(new DescriptiveResource("XML or something"));
 		beanFactory.registerBeanDefinition("bar", rbd);
@@ -378,7 +380,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test  // gh-25430
-	public void detectAliasOverride() {
+	void detectAliasOverride() {
 		AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
 		DefaultListableBeanFactory beanFactory = context.getDefaultListableBeanFactory();
 		beanFactory.setAllowBeanDefinitionOverriding(false);
@@ -390,7 +392,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void configurationClassesProcessedInCorrectOrder() {
+	void configurationClassesProcessedInCorrectOrder() {
 		beanFactory.registerBeanDefinition("config1", new RootBeanDefinition(OverridingSingletonBeanConfig.class));
 		beanFactory.registerBeanDefinition("config2", new RootBeanDefinition(SingletonBeanConfig.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
@@ -404,7 +406,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void configurationClassesWithValidOverridingForProgrammaticCall() {
+	void configurationClassesWithValidOverridingForProgrammaticCall() {
 		beanFactory.registerBeanDefinition("config1", new RootBeanDefinition(OverridingAgainSingletonBeanConfig.class));
 		beanFactory.registerBeanDefinition("config2", new RootBeanDefinition(OverridingSingletonBeanConfig.class));
 		beanFactory.registerBeanDefinition("config3", new RootBeanDefinition(SingletonBeanConfig.class));
@@ -419,7 +421,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void configurationClassesWithInvalidOverridingForProgrammaticCall() {
+	void configurationClassesWithInvalidOverridingForProgrammaticCall() {
 		beanFactory.registerBeanDefinition("config1", new RootBeanDefinition(InvalidOverridingSingletonBeanConfig.class));
 		beanFactory.registerBeanDefinition("config2", new RootBeanDefinition(OverridingSingletonBeanConfig.class));
 		beanFactory.registerBeanDefinition("config3", new RootBeanDefinition(SingletonBeanConfig.class));
@@ -435,7 +437,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test  // SPR-15384
-	public void nestedConfigurationClassesProcessedInCorrectOrder() {
+	void nestedConfigurationClassesProcessedInCorrectOrder() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(ConfigWithOrderedNestedClasses.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -448,7 +450,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test  // SPR-16734
-	public void innerConfigurationClassesProcessedInCorrectOrder() {
+	void innerConfigurationClassesProcessedInCorrectOrder() {
 		beanFactory.registerBeanDefinition("config", new RootBeanDefinition(ConfigWithOrderedInnerClasses.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -462,7 +464,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void scopedProxyTargetMarkedAsNonAutowireCandidate() {
+	void scopedProxyTargetMarkedAsNonAutowireCandidate() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -479,7 +481,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void processingAllowedOnlyOncePerProcessorRegistryPair() {
+	void processingAllowedOnlyOncePerProcessorRegistryPair() {
 		DefaultListableBeanFactory bf1 = new DefaultListableBeanFactory();
 		DefaultListableBeanFactory bf2 = new DefaultListableBeanFactory();
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
@@ -492,7 +494,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjection() {
+	void genericsBasedInjection() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -509,7 +511,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithScoped() {
+	void genericsBasedInjectionWithScoped() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -526,7 +528,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithScopedProxy() {
+	void genericsBasedInjectionWithScopedProxy() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -546,7 +548,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithScopedProxyUsingAsm() {
+	void genericsBasedInjectionWithScopedProxyUsingAsm() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -566,7 +568,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithImplTypeAtInjectionPoint() {
+	void genericsBasedInjectionWithImplTypeAtInjectionPoint() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -583,7 +585,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithFactoryBean() {
+	void genericsBasedInjectionWithFactoryBean() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -602,7 +604,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithRawMatch() {
+	void genericsBasedInjectionWithRawMatch() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawMatchingConfiguration.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -611,7 +613,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithWildcardMatch() {
+	void genericsBasedInjectionWithWildcardMatch() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(WildcardMatchingConfiguration.class));
 		ConfigurationClassPostProcessor pp = new ConfigurationClassPostProcessor();
 		pp.postProcessBeanFactory(beanFactory);
@@ -620,7 +622,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithWildcardWithExtendsMatch() {
+	void genericsBasedInjectionWithWildcardWithExtendsMatch() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(WildcardWithExtendsConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 
@@ -628,7 +630,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithWildcardWithGenericExtendsMatch() {
+	void genericsBasedInjectionWithWildcardWithGenericExtendsMatch() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(WildcardWithGenericExtendsConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 
@@ -636,12 +638,12 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithEarlyGenericsMatching() {
+	void genericsBasedInjectionWithEarlyGenericsMatching() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -653,13 +655,13 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatching() {
+	void genericsBasedInjectionWithLateGenericsMatching() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -671,12 +673,12 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithEarlyGenericsMatchingAndRawFactoryMethod() {
+	void genericsBasedInjectionWithEarlyGenericsMatchingAndRawFactoryMethod() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawFactoryMethodRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(0);
@@ -686,13 +688,13 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingAndRawFactoryMethod() {
+	void genericsBasedInjectionWithLateGenericsMatchingAndRawFactoryMethod() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawFactoryMethodRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -704,12 +706,12 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithEarlyGenericsMatchingAndRawInstance() {
+	void genericsBasedInjectionWithEarlyGenericsMatchingAndRawInstance() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawInstanceRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -721,13 +723,13 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingAndRawInstance() {
+	void genericsBasedInjectionWithLateGenericsMatchingAndRawInstance() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawInstanceRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -739,7 +741,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithEarlyGenericsMatchingOnCglibProxy() {
+	void genericsBasedInjectionWithEarlyGenericsMatchingOnCglibProxy() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -749,7 +751,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.registerSingleton("traceInterceptor", new DefaultPointcutAdvisor(new SimpleTraceInterceptor()));
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -763,7 +765,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingOnCglibProxy() {
+	void genericsBasedInjectionWithLateGenericsMatchingOnCglibProxy() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -774,7 +776,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -788,7 +790,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingOnCglibProxyAndRawFactoryMethod() {
+	void genericsBasedInjectionWithLateGenericsMatchingOnCglibProxyAndRawFactoryMethod() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawFactoryMethodRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -799,7 +801,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -813,7 +815,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingOnCglibProxyAndRawInstance() {
+	void genericsBasedInjectionWithLateGenericsMatchingOnCglibProxyAndRawInstance() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawInstanceRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -824,7 +826,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(Repository.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(Repository.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -838,7 +840,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithEarlyGenericsMatchingOnJdkProxy() {
+	void genericsBasedInjectionWithEarlyGenericsMatchingOnJdkProxy() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -847,7 +849,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.registerSingleton("traceInterceptor", new DefaultPointcutAdvisor(new SimpleTraceInterceptor()));
 
 		String[] beanNames = beanFactory.getBeanNamesForType(RepositoryInterface.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(RepositoryInterface.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -861,7 +863,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingOnJdkProxy() {
+	void genericsBasedInjectionWithLateGenericsMatchingOnJdkProxy() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -871,7 +873,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(RepositoryInterface.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(RepositoryInterface.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -885,7 +887,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingOnJdkProxyAndRawFactoryMethod() {
+	void genericsBasedInjectionWithLateGenericsMatchingOnJdkProxyAndRawFactoryMethod() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawFactoryMethodRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -895,7 +897,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(RepositoryInterface.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(RepositoryInterface.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -909,7 +911,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void genericsBasedInjectionWithLateGenericsMatchingOnJdkProxyAndRawInstance() {
+	void genericsBasedInjectionWithLateGenericsMatchingOnJdkProxyAndRawInstance() {
 		beanFactory.registerBeanDefinition("configClass", new RootBeanDefinition(RawInstanceRepositoryConfiguration.class));
 		new ConfigurationClassPostProcessor().postProcessBeanFactory(beanFactory);
 		DefaultAdvisorAutoProxyCreator autoProxyCreator = new DefaultAdvisorAutoProxyCreator();
@@ -919,7 +921,7 @@ public class ConfigurationClassPostProcessorTests {
 		beanFactory.preInstantiateSingletons();
 
 		String[] beanNames = beanFactory.getBeanNamesForType(RepositoryInterface.class);
-		assertThat(ObjectUtils.containsElement(beanNames, "stringRepo")).isTrue();
+		assertThat(beanNames).contains("stringRepo");
 
 		beanNames = beanFactory.getBeanNamesForType(ResolvableType.forClassWithGenerics(RepositoryInterface.class, String.class));
 		assertThat(beanNames.length).isEqualTo(1);
@@ -933,7 +935,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testSelfReferenceExclusionForFactoryMethodOnSameBean() {
+	void testSelfReferenceExclusionForFactoryMethodOnSameBean() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -947,7 +949,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testConfigWithDefaultMethods() {
+	void testConfigWithDefaultMethods() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -961,7 +963,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testConfigWithDefaultMethodsUsingAsm() {
+	void testConfigWithDefaultMethodsUsingAsm() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -975,7 +977,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testCircularDependency() {
+	void testCircularDependency() {
 		AutowiredAnnotationBeanPostProcessor bpp = new AutowiredAnnotationBeanPostProcessor();
 		bpp.setBeanFactory(beanFactory);
 		beanFactory.addBeanPostProcessor(bpp);
@@ -988,38 +990,38 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testCircularDependencyWithApplicationContext() {
+	void testCircularDependencyWithApplicationContext() {
 		assertThatExceptionOfType(BeanCreationException.class).isThrownBy(() ->
 				new AnnotationConfigApplicationContext(A.class, AStrich.class))
 			.withMessageContaining("Circular reference");
 	}
 
 	@Test
-	public void testPrototypeArgumentThroughBeanMethodCall() {
+	void testPrototypeArgumentThroughBeanMethodCall() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(BeanArgumentConfigWithPrototype.class);
 		ctx.getBean(FooFactory.class).createFoo(new BarArgument());
 	}
 
 	@Test
-	public void testSingletonArgumentThroughBeanMethodCall() {
+	void testSingletonArgumentThroughBeanMethodCall() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(BeanArgumentConfigWithSingleton.class);
 		ctx.getBean(FooFactory.class).createFoo(new BarArgument());
 	}
 
 	@Test
-	public void testNullArgumentThroughBeanMethodCall() {
+	void testNullArgumentThroughBeanMethodCall() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(BeanArgumentConfigWithNull.class);
 		ctx.getBean("aFoo");
 	}
 
 	@Test
-	public void testInjectionPointMatchForNarrowTargetReturnType() {
+	void testInjectionPointMatchForNarrowTargetReturnType() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(FooBarConfiguration.class);
 		assertThat(ctx.getBean(FooImpl.class).bar).isSameAs(ctx.getBean(BarImpl.class));
 	}
 
 	@Test
-	public void testVarargOnBeanMethod() {
+	void testVarargOnBeanMethod() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(VarargConfiguration.class, TestBean.class);
 		VarargConfiguration bean = ctx.getBean(VarargConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1028,7 +1030,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testEmptyVarargOnBeanMethod() {
+	void testEmptyVarargOnBeanMethod() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(VarargConfiguration.class);
 		VarargConfiguration bean = ctx.getBean(VarargConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1036,7 +1038,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testCollectionArgumentOnBeanMethod() {
+	void testCollectionArgumentOnBeanMethod() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(CollectionArgumentConfiguration.class, TestBean.class);
 		CollectionArgumentConfiguration bean = ctx.getBean(CollectionArgumentConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1045,7 +1047,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testEmptyCollectionArgumentOnBeanMethod() {
+	void testEmptyCollectionArgumentOnBeanMethod() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(CollectionArgumentConfiguration.class);
 		CollectionArgumentConfiguration bean = ctx.getBean(CollectionArgumentConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1053,7 +1055,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testMapArgumentOnBeanMethod() {
+	void testMapArgumentOnBeanMethod() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(MapArgumentConfiguration.class, DummyRunnable.class);
 		MapArgumentConfiguration bean = ctx.getBean(MapArgumentConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1062,7 +1064,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testEmptyMapArgumentOnBeanMethod() {
+	void testEmptyMapArgumentOnBeanMethod() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(MapArgumentConfiguration.class);
 		MapArgumentConfiguration bean = ctx.getBean(MapArgumentConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1070,7 +1072,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testCollectionInjectionFromSameConfigurationClass() {
+	void testCollectionInjectionFromSameConfigurationClass() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(CollectionInjectionConfiguration.class);
 		CollectionInjectionConfiguration bean = ctx.getBean(CollectionInjectionConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1079,7 +1081,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testMapInjectionFromSameConfigurationClass() {
+	void testMapInjectionFromSameConfigurationClass() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(MapInjectionConfiguration.class);
 		MapInjectionConfiguration bean = ctx.getBean(MapInjectionConfiguration.class);
 		assertThat(bean.testBeans).isNotNull();
@@ -1088,7 +1090,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testBeanLookupFromSameConfigurationClass() {
+	void testBeanLookupFromSameConfigurationClass() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(BeanLookupConfiguration.class);
 		BeanLookupConfiguration bean = ctx.getBean(BeanLookupConfiguration.class);
 		assertThat(bean.getTestBean()).isNotNull();
@@ -1096,7 +1098,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testNameClashBetweenConfigurationClassAndBean() {
+	void testNameClashBetweenConfigurationClassAndBean() {
 		assertThatExceptionOfType(BeanDefinitionStoreException.class).isThrownBy(() -> {
 				ApplicationContext ctx = new AnnotationConfigApplicationContext(MyTestBean.class);
 				ctx.getBean("myTestBean", TestBean.class);
@@ -1104,7 +1106,7 @@ public class ConfigurationClassPostProcessorTests {
 	}
 
 	@Test
-	public void testBeanDefinitionRegistryPostProcessorConfig() {
+	void testBeanDefinitionRegistryPostProcessorConfig() {
 		ApplicationContext ctx = new AnnotationConfigApplicationContext(BeanDefinitionRegistryPostProcessorConfig.class);
 		boolean condition = ctx.getBean("myTestBean") instanceof TestBean;
 		assertThat(condition).isTrue();

spring-context/src/test/java/org/springframework/context/annotation/PropertySourceAnnotationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,8 +18,10 @@ package org.springframework.context.annotation;
 
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
+import java.lang.annotation.Target;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.Properties;
@@ -31,6 +33,7 @@ import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.BeanDefinitionStoreException;
 import org.springframework.beans.factory.FactoryBean;
 import org.springframework.beans.testfixture.beans.TestBean;
+import org.springframework.context.ConfigurableApplicationContext;
 import org.springframework.core.annotation.AliasFor;
 import org.springframework.core.env.Environment;
 import org.springframework.core.env.MapPropertySource;
@@ -47,13 +50,13 @@ import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
  *
  * @author Chris Beams
  * @author Phillip Webb
+ * @author Sam Brannen
  * @since 3.1
  */
-public class PropertySourceAnnotationTests {
-
+class PropertySourceAnnotationTests {
 
 	@Test
-	public void withExplicitName() {
+	void withExplicitName() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
 		ctx.register(ConfigWithExplicitName.class);
 		ctx.refresh();
@@ -73,29 +76,25 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withImplicitName() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithImplicitName.class);
-		ctx.refresh();
+	void withImplicitName() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithImplicitName.class);
 		assertThat(ctx.getEnvironment().getPropertySources().contains("class path resource [org/springframework/context/annotation/p1.properties]")).as("property source p1 was not added").isTrue();
 		assertThat(ctx.getBean(TestBean.class).getName()).isEqualTo("p1TestBean");
 	}
 
 	@Test
-	public void withTestProfileBeans() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithTestProfileBeans.class);
-		ctx.refresh();
+	void withTestProfileBeans() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithTestProfileBeans.class);
 		assertThat(ctx.containsBean("testBean")).isTrue();
 		assertThat(ctx.containsBean("testProfileBean")).isTrue();
 	}
 
 	/**
-	 * Tests the LIFO behavior of @PropertySource annotaitons.
-	 * The last one registered should 'win'.
+	 * Tests the LIFO behavior of @PropertySource annotations.
+	 * <p>The last one registered should 'win'.
 	 */
 	@Test
-	public void orderingIsLifo() {
+	void orderingIsLifo() {
 		{
 			AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
 			ctx.register(ConfigWithImplicitName.class, P2Config.class);
@@ -114,7 +113,7 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withCustomFactory() {
+	void withCustomFactory() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
 		ctx.register(ConfigWithImplicitName.class, WithCustomFactory.class);
 		ctx.refresh();
@@ -122,7 +121,7 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withCustomFactoryAsMeta() {
+	void withCustomFactoryAsMeta() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
 		ctx.register(ConfigWithImplicitName.class, WithCustomFactoryAsMeta.class);
 		ctx.refresh();
@@ -130,59 +129,43 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withUnresolvablePlaceholder() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithUnresolvablePlaceholder.class);
-		try {
-			ctx.refresh();
-		}
-		catch (BeanDefinitionStoreException ex) {
-			assertThat(ex.getCause() instanceof IllegalArgumentException).isTrue();
-		}
+	void withUnresolvablePlaceholder() {
+		assertThatExceptionOfType(BeanDefinitionStoreException.class)
+			.isThrownBy(() -> new AnnotationConfigApplicationContext(ConfigWithUnresolvablePlaceholder.class))
+			.withCauseInstanceOf(IllegalArgumentException.class);
 	}
 
 	@Test
-	public void withUnresolvablePlaceholderAndDefault() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithUnresolvablePlaceholderAndDefault.class);
-		ctx.refresh();
+	void withUnresolvablePlaceholderAndDefault() {
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithUnresolvablePlaceholderAndDefault.class);
 		assertThat(ctx.getBean(TestBean.class).getName()).isEqualTo("p1TestBean");
 	}
 
 	@Test
-	public void withResolvablePlaceholder() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithResolvablePlaceholder.class);
+	void withResolvablePlaceholder() {
 		System.setProperty("path.to.properties", "org/springframework/context/annotation");
-		ctx.refresh();
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithResolvablePlaceholder.class);
 		assertThat(ctx.getBean(TestBean.class).getName()).isEqualTo("p1TestBean");
 		System.clearProperty("path.to.properties");
 	}
 
 	@Test
-	public void withResolvablePlaceholderAndFactoryBean() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithResolvablePlaceholderAndFactoryBean.class);
+	void withResolvablePlaceholderAndFactoryBean() {
 		System.setProperty("path.to.properties", "org/springframework/context/annotation");
-		ctx.refresh();
+		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithResolvablePlaceholderAndFactoryBean.class);
 		assertThat(ctx.getBean(TestBean.class).getName()).isEqualTo("p1TestBean");
 		System.clearProperty("path.to.properties");
 	}
 
 	@Test
-	public void withEmptyResourceLocations() {
-		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext();
-		ctx.register(ConfigWithEmptyResourceLocations.class);
-		try {
-			ctx.refresh();
-		}
-		catch (BeanDefinitionStoreException ex) {
-			assertThat(ex.getCause() instanceof IllegalArgumentException).isTrue();
-		}
+	void withEmptyResourceLocations() {
+		assertThatExceptionOfType(BeanDefinitionStoreException.class)
+			.isThrownBy(() -> new AnnotationConfigApplicationContext(ConfigWithEmptyResourceLocations.class))
+			.withCauseInstanceOf(IllegalArgumentException.class);
 	}
 
 	@Test
-	public void withNameAndMultipleResourceLocations() {
+	void withNameAndMultipleResourceLocations() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithNameAndMultipleResourceLocations.class);
 		assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
 		assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
@@ -191,7 +174,7 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withMultipleResourceLocations() {
+	void withMultipleResourceLocations() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithMultipleResourceLocations.class);
 		assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
 		assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
@@ -200,7 +183,7 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withPropertySources() {
+	void withRepeatedPropertySourcesInContainerAnnotation() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithPropertySources.class);
 		assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
 		assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
@@ -209,7 +192,43 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withNamedPropertySources() {
+	void withRepeatedPropertySources() {
+		try (AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithRepeatedPropertySourceAnnotations.class)) {
+			assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
+			assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
+			// p2 should 'win' as it was registered last
+			assertThat(ctx.getEnvironment().getProperty("testbean.name")).isEqualTo("p2TestBean");
+		}
+	}
+
+	@Test
+	void withRepeatedPropertySourcesOnComposedAnnotation() {
+		Class<?> configClass = ConfigWithRepeatedPropertySourceAnnotationsOnComposedAnnotation.class;
+		String key = "custom.config.package";
+
+		System.clearProperty(key);
+		try (ConfigurableApplicationContext ctx = new AnnotationConfigApplicationContext(configClass)) {
+			assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
+			assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
+			// p2 should 'win' as it was registered last
+			assertThat(ctx.getEnvironment().getProperty("testbean.name")).isEqualTo("p2TestBean");
+		}
+
+		System.setProperty(key, "org/springframework/context/annotation");
+		try (ConfigurableApplicationContext ctx = new AnnotationConfigApplicationContext(configClass)) {
+			assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
+			assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
+			assertThat(ctx.getEnvironment().containsProperty("from.p3")).isTrue();
+			// p3 should 'win' as it was registered last
+			assertThat(ctx.getEnvironment().getProperty("testbean.name")).isEqualTo("p3TestBean");
+		}
+		finally {
+			System.clearProperty(key);
+		}
+	}
+
+	@Test
+	void withNamedPropertySources() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithNamedPropertySources.class);
 		assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
 		assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
@@ -218,21 +237,21 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void withMissingPropertySource() {
-		assertThatExceptionOfType(BeanDefinitionStoreException.class).isThrownBy(() ->
-				new AnnotationConfigApplicationContext(ConfigWithMissingPropertySource.class))
+	void withMissingPropertySource() {
+		assertThatExceptionOfType(BeanDefinitionStoreException.class)
+			.isThrownBy(() -> new AnnotationConfigApplicationContext(ConfigWithMissingPropertySource.class))
 			.withCauseInstanceOf(FileNotFoundException.class);
 	}
 
 	@Test
-	public void withIgnoredPropertySource() {
+	void withIgnoredPropertySource() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithIgnoredPropertySource.class);
 		assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
 		assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
 	}
 
 	@Test
-	public void withSameSourceImportedInDifferentOrder() {
+	void withSameSourceImportedInDifferentOrder() {
 		AnnotationConfigApplicationContext ctx = new AnnotationConfigApplicationContext(ConfigWithSameSourceImportedInDifferentOrder.class);
 		assertThat(ctx.getEnvironment().containsProperty("from.p1")).isTrue();
 		assertThat(ctx.getEnvironment().containsProperty("from.p2")).isTrue();
@@ -240,7 +259,7 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void orderingWithAndWithoutNameAndMultipleResourceLocations() {
+	void orderingWithAndWithoutNameAndMultipleResourceLocations() {
 		// SPR-10820: p2 should 'win' as it was registered last
 		AnnotationConfigApplicationContext ctxWithName = new AnnotationConfigApplicationContext(ConfigWithNameAndMultipleResourceLocations.class);
 		AnnotationConfigApplicationContext ctxWithoutName = new AnnotationConfigApplicationContext(ConfigWithMultipleResourceLocations.class);
@@ -249,14 +268,14 @@ public class PropertySourceAnnotationTests {
 	}
 
 	@Test
-	public void orderingWithAndWithoutNameAndFourResourceLocations() {
+	void orderingWithAndWithoutNameAndFourResourceLocations() {
 		// SPR-12198: p4 should 'win' as it was registered last
 		AnnotationConfigApplicationContext ctxWithoutName = new AnnotationConfigApplicationContext(ConfigWithFourResourceLocations.class);
 		assertThat(ctxWithoutName.getEnvironment().getProperty("testbean.name")).isEqualTo("p4TestBean");
 	}
 
 	@Test
-	public void orderingDoesntReplaceExisting() throws Exception {
+	void orderingDoesntReplaceExisting() throws Exception {
 		// SPR-12198: mySource should 'win' as it was registered manually
 		AnnotationConfigApplicationContext ctxWithoutName = new AnnotationConfigApplicationContext();
 		MapPropertySource mySource = new MapPropertySource("mine", Collections.singletonMap("testbean.name", "myTestBean"));
@@ -267,51 +286,51 @@ public class PropertySourceAnnotationTests {
 
 	}
 
+
 	@Configuration
-	@PropertySource(value="classpath:${unresolvable}/p1.properties")
+	@PropertySource("classpath:${unresolvable}/p1.properties")
 	static class ConfigWithUnresolvablePlaceholder {
 	}
 
 
 	@Configuration
-	@PropertySource(value="classpath:${unresolvable:org/springframework/context/annotation}/p1.properties")
+	@PropertySource("classpath:${unresolvable:org/springframework/context/annotation}/p1.properties")
 	static class ConfigWithUnresolvablePlaceholderAndDefault {
 
 		@Inject Environment env;
 
 		@Bean
-		public TestBean testBean() {
+		TestBean testBean() {
 			return new TestBean(env.getProperty("testbean.name"));
 		}
 	}
 
 
 	@Configuration
-	@PropertySource(value="classpath:${path.to.properties}/p1.properties")
+	@PropertySource("classpath:${path.to.properties}/p1.properties")
 	static class ConfigWithResolvablePlaceholder {
 
 		@Inject Environment env;
 
 		@Bean
-		public TestBean testBean() {
+		TestBean testBean() {
 			return new TestBean(env.getProperty("testbean.name"));
 		}
 	}
 
 
 	@Configuration
-	@PropertySource(value="classpath:${path.to.properties}/p1.properties")
+	@PropertySource("classpath:${path.to.properties}/p1.properties")
 	static class ConfigWithResolvablePlaceholderAndFactoryBean {
 
 		@Inject Environment env;
 
-		@SuppressWarnings("rawtypes")
 		@Bean
-		public FactoryBean testBean() {
+		FactoryBean<TestBean> testBean() {
 			final String name = env.getProperty("testbean.name");
-			return new FactoryBean() {
+			return new FactoryBean<TestBean>() {
 				@Override
-				public Object getObject() {
+				public TestBean getObject() {
 					return new TestBean(name);
 				}
 				@Override
@@ -334,7 +353,7 @@ public class PropertySourceAnnotationTests {
 		@Inject Environment env;
 
 		@Bean
-		public TestBean testBean() {
+		TestBean testBean() {
 			return new TestBean(env.getProperty("testbean.name"));
 		}
 	}
@@ -347,7 +366,7 @@ public class PropertySourceAnnotationTests {
 		@Inject Environment env;
 
 		@Bean
-		public TestBean testBean() {
+		TestBean testBean() {
 			return new TestBean(env.getProperty("testbean.name"));
 		}
 	}
@@ -361,7 +380,7 @@ public class PropertySourceAnnotationTests {
 		@Inject Environment env;
 
 		@Bean @Profile("test")
-		public TestBean testBean() {
+		TestBean testBean() {
 			return new TestBean(env.getProperty("testbean.name"));
 		}
 	}
@@ -380,21 +399,21 @@ public class PropertySourceAnnotationTests {
 
 
 	@Configuration
-	@MyPropertySource(value = "classpath:org/springframework/context/annotation/p2.properties")
+	@MyPropertySource("classpath:org/springframework/context/annotation/p2.properties")
 	static class WithCustomFactoryAsMeta {
 	}
 
 
 	@Retention(RetentionPolicy.RUNTIME)
 	@PropertySource(value = {}, factory = MyCustomFactory.class)
-	public @interface MyPropertySource {
+	@interface MyPropertySource {
 
 		@AliasFor(annotation = PropertySource.class)
 		String value();
 	}
 
 
-	public static class MyCustomFactory implements PropertySourceFactory {
+	static class MyCustomFactory implements PropertySourceFactory {
 
 		@Override
 		public org.springframework.core.env.PropertySource<?> createPropertySource(String name, EncodedResource resource) throws IOException {
@@ -422,11 +441,10 @@ public class PropertySourceAnnotationTests {
 
 
 	@Configuration
-	@PropertySource(
-			value = {
-					"classpath:org/springframework/context/annotation/p1.properties",
-					"classpath:org/springframework/context/annotation/p2.properties"
-			})
+	@PropertySource({
+		"classpath:org/springframework/context/annotation/p1.properties",
+		"classpath:org/springframework/context/annotation/p2.properties"
+	})
 	static class ConfigWithMultipleResourceLocations {
 	}
 
@@ -434,12 +452,33 @@ public class PropertySourceAnnotationTests {
 	@Configuration
 	@PropertySources({
 		@PropertySource("classpath:org/springframework/context/annotation/p1.properties"),
-		@PropertySource("classpath:${base.package}/p2.properties"),
+		@PropertySource("classpath:${base.package}/p2.properties")
 	})
 	static class ConfigWithPropertySources {
 	}
 
 
+	@Configuration
+	@PropertySource("classpath:org/springframework/context/annotation/p1.properties")
+	@PropertySource(value = "classpath:${base.package}/p2.properties", ignoreResourceNotFound = true)
+	static class ConfigWithRepeatedPropertySourceAnnotations {
+	}
+
+
+	@Target(ElementType.TYPE)
+	@Retention(RetentionPolicy.RUNTIME)
+	@Configuration
+	@PropertySource("classpath:org/springframework/context/annotation/p1.properties")
+	@PropertySource(value = "classpath:${base.package}/p2.properties", ignoreResourceNotFound = true)
+	@PropertySource(value = "classpath:${custom.config.package:bogus/config}/p3.properties", ignoreResourceNotFound = true)
+	@interface ComposedConfiguration {
+	}
+
+	@ComposedConfiguration
+	static class ConfigWithRepeatedPropertySourceAnnotationsOnComposedAnnotation {
+	}
+
+
 	@Configuration
 	@PropertySources({
 		@PropertySource(name = "psName", value = "classpath:org/springframework/context/annotation/p1.properties"),
@@ -471,7 +510,7 @@ public class PropertySourceAnnotationTests {
 
 
 	@Configuration
-	@PropertySource(value = {})
+	@PropertySource({})
 	static class ConfigWithEmptyResourceLocations {
 	}
 
@@ -482,7 +521,7 @@ public class PropertySourceAnnotationTests {
 		@PropertySource("classpath:org/springframework/context/annotation/p2.properties")
 	})
 	@Configuration
-	public static class ConfigWithSameSourceImportedInDifferentOrder {
+	static class ConfigWithSameSourceImportedInDifferentOrder {
 
 	}
 
@@ -492,18 +531,17 @@ public class PropertySourceAnnotationTests {
 		@PropertySource("classpath:org/springframework/context/annotation/p2.properties"),
 		@PropertySource("classpath:org/springframework/context/annotation/p1.properties")
 	})
-	public static class ConfigImportedWithSameSourceImportedInDifferentOrder {
+	static class ConfigImportedWithSameSourceImportedInDifferentOrder {
 	}
 
 
 	@Configuration
-	@PropertySource(
-			value = {
-					"classpath:org/springframework/context/annotation/p1.properties",
-					"classpath:org/springframework/context/annotation/p2.properties",
-					"classpath:org/springframework/context/annotation/p3.properties",
-					"classpath:org/springframework/context/annotation/p4.properties"
-			})
+	@PropertySource({
+		"classpath:org/springframework/context/annotation/p1.properties",
+		"classpath:org/springframework/context/annotation/p2.properties",
+		"classpath:org/springframework/context/annotation/p3.properties",
+		"classpath:org/springframework/context/annotation/p4.properties"
+	})
 	static class ConfigWithFourResourceLocations {
 	}
 

spring-context/src/test/java/org/springframework/context/event/PayloadApplicationEventTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -49,9 +49,11 @@ public class PayloadApplicationEventTests {
 	public void testProgrammaticEventListener() {
 		List<Auditable> events = new ArrayList<>();
 		ApplicationListener<AuditablePayloadEvent<String>> listener = events::add;
+		ApplicationListener<AuditablePayloadEvent<Integer>> mismatch = (event -> event.getPayload().intValue());
 
 		ConfigurableApplicationContext ac = new GenericApplicationContext();
 		ac.addApplicationListener(listener);
+		ac.addApplicationListener(mismatch);
 		ac.refresh();
 
 		AuditablePayloadEvent<String> event = new AuditablePayloadEvent<>(this, "xyz");
@@ -63,9 +65,11 @@ public class PayloadApplicationEventTests {
 	public void testProgrammaticPayloadListener() {
 		List<String> events = new ArrayList<>();
 		ApplicationListener<PayloadApplicationEvent<String>> listener = ApplicationListener.forPayload(events::add);
+		ApplicationListener<PayloadApplicationEvent<Integer>> mismatch = ApplicationListener.forPayload(payload -> payload.intValue());
 
 		ConfigurableApplicationContext ac = new GenericApplicationContext();
 		ac.addApplicationListener(listener);
+		ac.addApplicationListener(mismatch);
 		ac.refresh();
 
 		AuditablePayloadEvent<String> event = new AuditablePayloadEvent<>(this, "xyz");

spring-context/src/test/java/org/springframework/scheduling/support/BitsCronFieldTests.java

@@ -25,18 +25,47 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 
 /**
+ * Unit tests for {@link BitsCronField}.
+ *
  * @author Arjen Poutsma
+ * @author Sam Brannen
  */
-public class BitsCronFieldTests {
+class BitsCronFieldTests {
 
 	@Test
 	void parse() {
 		assertThat(BitsCronField.parseSeconds("42")).has(clearRange(0, 41)).has(set(42)).has(clearRange(43, 59));
-		assertThat(BitsCronField.parseMinutes("1,2,5,9")).has(clear(0)).has(set(1, 2)).has(clearRange(3,4)).has(set(5)).has(clearRange(6,8)).has(set(9)).has(clearRange(10,59));
 		assertThat(BitsCronField.parseSeconds("0-4,8-12")).has(setRange(0, 4)).has(clearRange(5,7)).has(setRange(8, 12)).has(clearRange(13,59));
-		assertThat(BitsCronField.parseHours("0-23/2")).has(set(0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22)).has(clear(1,3,5,7,9,11,13,15,17,19,21,23));
-		assertThat(BitsCronField.parseDaysOfWeek("0")).has(clearRange(0, 6)).has(set(7, 7));
 		assertThat(BitsCronField.parseSeconds("57/2")).has(clearRange(0, 56)).has(set(57)).has(clear(58)).has(set(59));
+
+		assertThat(BitsCronField.parseMinutes("30")).has(set(30)).has(clearRange(1, 29)).has(clearRange(31, 59));
+
+		assertThat(BitsCronField.parseHours("23")).has(set(23)).has(clearRange(0, 23));
+		assertThat(BitsCronField.parseHours("0-23/2")).has(set(0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22)).has(clear(1,3,5,7,9,11,13,15,17,19,21,23));
+
+		assertThat(BitsCronField.parseDaysOfMonth("1")).has(set(1)).has(clearRange(2, 31));
+
+		assertThat(BitsCronField.parseMonth("1")).has(set(1)).has(clearRange(2, 12));
+
+		assertThat(BitsCronField.parseDaysOfWeek("0")).has(set(7, 7)).has(clearRange(0, 6));
+	}
+
+	@Test
+	void parseLists() {
+		assertThat(BitsCronField.parseSeconds("15,30")).has(set(15, 30)).has(clearRange(1, 15)).has(clearRange(31, 59));
+		assertThat(BitsCronField.parseMinutes("1,2,5,9")).has(set(1, 2, 5, 9)).has(clear(0)).has(clearRange(3, 4)).has(clearRange(6, 8)).has(clearRange(10, 59));
+		assertThat(BitsCronField.parseHours("1,2,3")).has(set(1, 2, 3)).has(clearRange(4, 23));
+		assertThat(BitsCronField.parseDaysOfMonth("1,2,3")).has(set(1, 2, 3)).has(clearRange(4, 31));
+		assertThat(BitsCronField.parseMonth("1,2,3")).has(set(1, 2, 3)).has(clearRange(4, 12));
+		assertThat(BitsCronField.parseDaysOfWeek("1,2,3")).has(set(1, 2, 3)).has(clearRange(4, 7));
+
+		assertThat(BitsCronField.parseMinutes("5,10-30/2"))
+				.has(clearRange(0, 5))
+				.has(set(5))
+				.has(clearRange(6,10))
+				.has(set(10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30))
+				.has(clear(11, 13, 15, 17, 19, 21, 23, 25, 27, 29))
+				.has(clearRange(31, 60));
 	}
 
 	@Test

spring-context/src/test/java/org/springframework/scheduling/support/CronExpressionTests.java

@@ -31,6 +31,7 @@ import org.junit.jupiter.api.Test;
 import static java.time.DayOfWeek.FRIDAY;
 import static java.time.DayOfWeek.MONDAY;
 import static java.time.DayOfWeek.SUNDAY;
+import static java.time.DayOfWeek.THURSDAY;
 import static java.time.DayOfWeek.TUESDAY;
 import static java.time.DayOfWeek.WEDNESDAY;
 import static java.time.temporal.TemporalAdjusters.next;
@@ -116,6 +117,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withMinute(10);
 		LocalDateTime expected = last.plusMinutes(1).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -149,6 +151,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.of(year, 10, 30, 11, 1);
 		LocalDateTime expected = last.withHour(12).withMinute(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -173,6 +176,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withDayOfMonth(1);
 		LocalDateTime expected = last.plusDays(1).withHour(0).withMinute(0).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -207,6 +211,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withMonth(9).withDayOfMonth(30);
 		LocalDateTime expected = LocalDateTime.of(last.getYear(), 10, 1, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -222,6 +227,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withMonth(8).withDayOfMonth(30);
 		LocalDateTime expected = last.plusDays(1).withHour(0).withMinute(0).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -237,6 +243,7 @@ class CronExpressionTests {
 		ZonedDateTime last = ZonedDateTime.now(ZoneId.of("CET")).withMonth(10).withDayOfMonth(30);
 		ZonedDateTime expected = last.withDayOfMonth(31).withHour(0).withMinute(0).withSecond(0).withNano(0);
 		ZonedDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -251,6 +258,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withMonth(10).withDayOfMonth(30);
 		LocalDateTime expected = LocalDateTime.of(last.getYear(), 11, 1, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -265,6 +273,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withYear(2010).withMonth(12).withDayOfMonth(31);
 		LocalDateTime expected = LocalDateTime.of(2011, 1, 1, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -297,6 +306,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().with(next(MONDAY));
 		LocalDateTime expected = last.plusDays(1).withHour(0).withMinute(0).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 		assertThat(actual.getDayOfWeek()).isEqualTo(TUESDAY);
 	}
@@ -308,6 +318,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().with(next(WEDNESDAY));
 		LocalDateTime expected = last.plusDays(6).withHour(0).withMinute(0).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 		assertThat(actual.getDayOfWeek()).isEqualTo(TUESDAY);
 	}
@@ -319,6 +330,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withMinute(4).withSecond(54);
 		LocalDateTime expected = last.plusMinutes(1).withSecond(55).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -333,6 +345,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withHour(9).withSecond(54);
 		LocalDateTime expected = last.plusHours(1).withMinute(0).withSecond(55).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -347,6 +360,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withHour(9).withMinute(4);
 		LocalDateTime expected = last.plusHours(1).plusMinutes(1).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -362,6 +376,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withDayOfMonth(2).withSecond(54);
 		LocalDateTime expected = last.plusDays(1).withHour(0).withMinute(0).withSecond(55).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -376,6 +391,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withMonth(10).withDayOfMonth(2);
 		LocalDateTime expected = LocalDateTime.of(last.getYear(), 11, 3, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -398,6 +414,7 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.now().withYear(2007).withMonth(2).withDayOfMonth(10);
 		LocalDateTime expected = LocalDateTime.of(2008, 2, 29, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -413,12 +430,14 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.of(LocalDate.of(2009, 9, 26), LocalTime.now());
 		LocalDateTime expected = last.plusDays(2).withHour(7).withMinute(0).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		// Next day is a week day so add one
 		last = actual;
 		expected = expected.plusDays(1);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -433,12 +452,14 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.of(LocalDate.of(2010, 12, 30), LocalTime.now());
 		LocalDateTime expected = last.plusMonths(1).withHour(23).withMinute(30).withSecond(0).withSecond(0).withNano(0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		// Next trigger is 3 months later
 		last = actual;
 		expected = expected.plusMonths(3);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -485,11 +506,13 @@ class CronExpressionTests {
 		LocalDateTime expected = LocalDateTime.of(last.getYear() + 1, 1, 1, 0, 0);
 
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = expected.plusYears(1);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -513,11 +536,13 @@ class CronExpressionTests {
 		LocalDateTime expected = LocalDateTime.of(last.getYear(), 11, 1, 0, 0);
 
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = expected.plusMonths(1);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -534,11 +559,13 @@ class CronExpressionTests {
 		LocalDateTime expected = last.with(next(SUNDAY)).withHour(0).withMinute(0).withSecond(0).withNano(0);
 
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = expected.plusWeeks(1);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -555,11 +582,13 @@ class CronExpressionTests {
 		LocalDateTime expected = last.plusDays(1).withHour(0).withMinute(0).withSecond(0).withNano(0);
 
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = expected.plusDays(1);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -583,11 +612,13 @@ class CronExpressionTests {
 		LocalDateTime expected = last.plusHours(1).withMinute(0).withSecond(0).withNano(0);
 
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = expected.plusHours(1);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -603,16 +634,19 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.of(LocalDate.of(2008, 1, 4), LocalTime.now());
 		LocalDateTime expected = LocalDateTime.of(2008, 1, 31, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = LocalDateTime.of(2008, 2, 29, 0, 0);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = LocalDateTime.of(2008, 3, 31, 0, 0);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -628,16 +662,19 @@ class CronExpressionTests {
 		LocalDateTime last = LocalDateTime.of(LocalDate.of(2008, 1, 4), LocalTime.now());
 		LocalDateTime expected = LocalDateTime.of(2008, 1, 28, 0, 0);
 		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = LocalDateTime.of(2008, 2, 26, 0, 0);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
 		expected = LocalDateTime.of(2008, 3, 28, 0, 0);
 		actual = expression.next(last);
+		assertThat(actual).isNotNull();
 		assertThat(actual).isEqualTo(expected);
 
 		last = actual;
@@ -1042,4 +1079,62 @@ class CronExpressionTests {
 		assertThat(actual).isEqualTo(expected);
 		assertThat(actual.getDayOfWeek()).isEqualTo(WEDNESDAY);
 	}
+
+	@Test
+	void dayOfMonthListWithQuartz() {
+		CronExpression expression = CronExpression.parse("0 0 0 1W,15,LW * ?");
+
+		LocalDateTime last = LocalDateTime.of(2019, 12, 30, 0, 0);
+		LocalDateTime expected = LocalDateTime.of(2019, 12, 31, 0, 0);
+		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+		assertThat(actual).is(weekday);
+
+		last = actual;
+		expected = LocalDateTime.of(2020, 1, 1, 0, 0);
+		actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+		assertThat(actual).is(weekday);
+
+		last = actual;
+		expected = LocalDateTime.of(2020, 1, 15, 0, 0);
+		actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+
+		last = actual;
+		expected = LocalDateTime.of(2020, 1, 31, 0, 0);
+		actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+		assertThat(actual).is(weekday);
+	}
+
+	@Test
+	void dayOfWeekListWithQuartz() {
+		CronExpression expression = CronExpression.parse("0 0 0 ? * THU#1,THU#3,THU#5");
+
+		LocalDateTime last = LocalDateTime.of(2019, 12, 31, 0, 0);
+		LocalDateTime expected = LocalDateTime.of(2020, 1, 2, 0, 0);
+		LocalDateTime actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+		assertThat(actual.getDayOfWeek()).isEqualTo(THURSDAY);
+
+		last = actual;
+		expected = LocalDateTime.of(2020, 1, 16, 0, 0);
+		actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+		assertThat(actual.getDayOfWeek()).isEqualTo(THURSDAY);
+
+		last = actual;
+		expected = LocalDateTime.of(2020, 1, 30, 0, 0);
+		actual = expression.next(last);
+		assertThat(actual).isNotNull();
+		assertThat(actual).isEqualTo(expected);
+		assertThat(actual.getDayOfWeek()).isEqualTo(THURSDAY);
+	}
 }

spring-context/src/test/java/org/springframework/scheduling/support/QuartzCronFieldTests.java

@@ -25,6 +25,8 @@ import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
 
 /**
+ * Unit tests for {@link QuartzCronField}.
+ *
  * @author Arjen Poutsma
  */
 class QuartzCronFieldTests {
@@ -95,6 +97,7 @@ class QuartzCronFieldTests {
 		assertThatIllegalArgumentException().isThrownBy(() -> QuartzCronField.parseDaysOfWeek("1#L"));
 		assertThatIllegalArgumentException().isThrownBy(() -> QuartzCronField.parseDaysOfWeek("L#1"));
 		assertThatIllegalArgumentException().isThrownBy(() -> QuartzCronField.parseDaysOfWeek("8#1"));
+		assertThatIllegalArgumentException().isThrownBy(() -> QuartzCronField.parseDaysOfWeek("2#1,2#3,2#5"));
 	}
 
 }

spring-context/src/test/resources/org/springframework/context/annotation/p3.properties

@@ -1 +1,2 @@
 testbean.name=p3TestBean
+from.p3=p3Value

spring-core/kotlin-coroutines/src/main/kotlin/org/springframework/core/CoroutinesUtils.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -58,10 +58,10 @@ internal fun <T: Any> monoToDeferred(source: Mono<T>) =
  * @since 5.2
  */
 @Suppress("UNCHECKED_CAST")
-fun invokeSuspendingFunction(method: Method, bean: Any, vararg args: Any?): Publisher<*> {
+fun invokeSuspendingFunction(method: Method, target: Any, vararg args: Any?): Publisher<*> {
 	val function = method.kotlinFunction!!
 	val mono = mono(Dispatchers.Unconfined) {
-		function.callSuspend(bean, *args.sliceArray(0..(args.size-2))).let { if (it == Unit) null else it }
+		function.callSuspend(target, *args.sliceArray(0..(args.size-2))).let { if (it == Unit) null else it }
 	}.onErrorMap(InvocationTargetException::class.java) { it.targetException }
 	return if (function.returnType.classifier == Flow::class) {
 		mono.flatMapMany { (it as Flow<Any>).asFlux() }

spring-core/src/main/java/org/springframework/asm/AnnotationVisitor.java

@@ -129,9 +129,9 @@ public abstract class AnnotationVisitor {
   }
 
   /**
-   * Visits an array value of the annotation. Note that arrays of primitive types (such as byte,
+   * Visits an array value of the annotation. Note that arrays of primitive values (such as byte,
    * boolean, short, char, int, long, float or double) can be passed as value to {@link #visit
-   * visit}. This is what {@link ClassReader} does.
+   * visit}. This is what {@link ClassReader} does for non empty arrays of primitive values.
    *
    * @param name the value name.
    * @return a visitor to visit the actual array value elements, or {@literal null} if this visitor

spring-core/src/main/java/org/springframework/asm/ClassReader.java

@@ -100,8 +100,10 @@ public class ClassReader {
   @Deprecated
   // DontCheck(MemberName): can't be renamed (for backward binary compatibility).
   public final byte[] b;
+
   /** The offset in bytes of the ClassFile's access_flags field. */
   public final int header;
+
   /**
    * A byte array containing the JVMS ClassFile structure to be parsed. <i>The content of this array
    * must not be modified. This field is intended for {@link Attribute} sub classes, and is normally
@@ -112,6 +114,7 @@ public class ClassReader {
    * ClassFile element offsets within this byte array.
    */
   final byte[] classFileBuffer;
+
   /**
    * The offset in bytes, in {@link #classFileBuffer}, of each cp_info entry of the ClassFile's
    * constant_pool array, <i>plus one</i>. In other words, the offset of constant pool entry i is
@@ -119,16 +122,19 @@ public class ClassReader {
    * 1].
    */
   private final int[] cpInfoOffsets;
+
   /**
    * The String objects corresponding to the CONSTANT_Utf8 constant pool items. This cache avoids
    * multiple parsing of a given CONSTANT_Utf8 constant pool item.
    */
   private final String[] constantUtf8Values;
+
   /**
    * The ConstantDynamic objects corresponding to the CONSTANT_Dynamic constant pool items. This
    * cache avoids multiple parsing of a given CONSTANT_Dynamic constant pool item.
    */
   private final ConstantDynamic[] constantDynamicValues;
+
   /**
    * The start offsets in {@link #classFileBuffer} of each element of the bootstrap_methods array
    * (in the BootstrapMethods attribute).
@@ -137,6 +143,7 @@ public class ClassReader {
    *     4.7.23</a>
    */
   private final int[] bootstrapMethodOffsets;
+
   /**
    * A conservative estimate of the maximum length of the strings contained in the constant pool of
    * the class.
@@ -184,7 +191,7 @@ public class ClassReader {
     this.b = classFileBuffer;
     // Check the class' major_version. This field is after the magic and minor_version fields, which
     // use 4 and 2 bytes respectively.
-    if (checkClassVersion && readShort(classFileOffset + 6) > Opcodes.V16) {
+    if (checkClassVersion && readShort(classFileOffset + 6) > Opcodes.V17) {
       throw new IllegalArgumentException(
           "Unsupported class file major version " + readShort(classFileOffset + 6));
     }
@@ -499,6 +506,9 @@ public class ClassReader {
       } else if (Constants.SYNTHETIC.equals(attributeName)) {
         accessFlags |= Opcodes.ACC_SYNTHETIC;
       } else if (Constants.SOURCE_DEBUG_EXTENSION.equals(attributeName)) {
+        if (attributeLength > classFileBuffer.length - currentAttributeOffset) {
+          throw new IllegalArgumentException();
+        }
         sourceDebugExtension =
             readUtf(currentAttributeOffset, attributeLength, new char[attributeLength]);
       } else if (Constants.RUNTIME_INVISIBLE_ANNOTATIONS.equals(attributeName)) {
@@ -1509,6 +1519,9 @@ public class ClassReader {
     final int maxLocals = readUnsignedShort(currentOffset + 2);
     final int codeLength = readInt(currentOffset + 4);
     currentOffset += 8;
+    if (codeLength > classFileBuffer.length - currentOffset) {
+      throw new IllegalArgumentException();
+    }
 
     // Read the bytecode 'code' array to create a label for each referenced instruction.
     final int bytecodeStartOffset = currentOffset;
@@ -2965,7 +2978,7 @@ public class ClassReader {
       // Parse the array_value array.
       while (numElementValuePairs-- > 0) {
         currentOffset =
-            readElementValue(annotationVisitor, currentOffset, /* elementName = */ null, charBuffer);
+            readElementValue(annotationVisitor, currentOffset, /* elementName= */ null, charBuffer);
       }
     }
     if (annotationVisitor != null) {

spring-core/src/main/java/org/springframework/asm/Opcodes.java

@@ -132,7 +132,7 @@ public interface Opcodes {
    * <pre>
    * public class StuffVisitor {
    *   &#64;Deprecated public void visitOldStuff(int arg, ...) {
-   *     visitNewStuf(arg | SOURCE_DEPRECATED, ...);
+   *     visitNewStuff(arg | SOURCE_DEPRECATED, ...);
    *   }
    *   public void visitNewStuff(int argAndSource...) {
    *     if ((argAndSource & SOURCE_DEPRECATED) == 0) {
@@ -154,7 +154,7 @@ public interface Opcodes {
    * <p>and there are two cases:
    *
    * <ul>
-   *   <li>call visitOldSuff: in the call to super.visitOldStuff, the source is set to
+   *   <li>call visitOldStuff: in the call to super.visitOldStuff, the source is set to
    *       SOURCE_DEPRECATED and visitNewStuff is called. Here 'do stuff' is run because the source
    *       was previously set to SOURCE_DEPRECATED, and execution eventually returns to
    *       UserStuffVisitor.visitOldStuff, where 'do user stuff' is run.
@@ -281,6 +281,7 @@ public interface Opcodes {
   int V14 = 0 << 16 | 58;
   int V15 = 0 << 16 | 59;
   int V16 = 0 << 16 | 60;
+  int V17 = 0 << 16 | 61;
 
   /**
    * Version flag indicating that the class is using 'preview' features.

spring-core/src/main/java/org/springframework/core/AttributeAccessor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,20 +16,24 @@
 
 package org.springframework.core;
 
+import java.util.function.Function;
+
 import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
 
 /**
  * Interface defining a generic contract for attaching and accessing metadata
  * to/from arbitrary objects.
  *
  * @author Rob Harrop
+ * @author Sam Brannen
  * @since 2.0
  */
 public interface AttributeAccessor {
 
 	/**
 	 * Set the attribute defined by {@code name} to the supplied {@code value}.
-	 * If {@code value} is {@code null}, the attribute is {@link #removeAttribute removed}.
+	 * <p>If {@code value} is {@code null}, the attribute is {@link #removeAttribute removed}.
 	 * <p>In general, users should take care to prevent overlaps with other
 	 * metadata attributes by using fully-qualified names, perhaps using
 	 * class or package names as prefix.
@@ -40,16 +44,48 @@ public interface AttributeAccessor {
 
 	/**
 	 * Get the value of the attribute identified by {@code name}.
-	 * Return {@code null} if the attribute doesn't exist.
+	 * <p>Return {@code null} if the attribute doesn't exist.
 	 * @param name the unique attribute key
 	 * @return the current value of the attribute, if any
 	 */
 	@Nullable
 	Object getAttribute(String name);
 
+	/**
+	 * Compute a new value for the attribute identified by {@code name} if
+	 * necessary and {@linkplain #setAttribute set} the new value in this
+	 * {@code AttributeAccessor}.
+	 * <p>If a value for the attribute identified by {@code name} already exists
+	 * in this {@code AttributeAccessor}, the existing value will be returned
+	 * without applying the supplied compute function.
+	 * <p>The default implementation of this method is not thread safe but can
+	 * overridden by concrete implementations of this interface.
+	 * @param <T> the type of the attribute value
+	 * @param name the unique attribute key
+	 * @param computeFunction a function that computes a new value for the attribute
+	 * name; the function must not return a {@code null} value
+	 * @return the existing value or newly computed value for the named attribute
+	 * @see #getAttribute(String)
+	 * @see #setAttribute(String, Object)
+	 * @since 5.3.3
+	 */
+	@SuppressWarnings("unchecked")
+	default <T> T computeAttribute(String name, Function<String, T> computeFunction) {
+		Assert.notNull(name, "Name must not be null");
+		Assert.notNull(computeFunction, "Compute function must not be null");
+		Object value = getAttribute(name);
+		if (value == null) {
+			value = computeFunction.apply(name);
+			Assert.state(value != null,
+					() -> String.format("Compute function must not return null for attribute named '%s'", name));
+			setAttribute(name, value);
+		}
+		return (T) value;
+	}
+
 	/**
 	 * Remove the attribute identified by {@code name} and return its value.
-	 * Return {@code null} if no attribute under {@code name} is found.
+	 * <p>Return {@code null} if no attribute under {@code name} is found.
 	 * @param name the unique attribute key
 	 * @return the last value of the attribute, if any
 	 */
@@ -58,7 +94,7 @@ public interface AttributeAccessor {
 
 	/**
 	 * Return {@code true} if the attribute identified by {@code name} exists.
-	 * Otherwise return {@code false}.
+	 * <p>Otherwise return {@code false}.
 	 * @param name the unique attribute key
 	 */
 	boolean hasAttribute(String name);

spring-core/src/main/java/org/springframework/core/AttributeAccessorSupport.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@ package org.springframework.core;
 import java.io.Serializable;
 import java.util.LinkedHashMap;
 import java.util.Map;
+import java.util.function.Function;
 
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
@@ -32,6 +33,7 @@ import org.springframework.util.StringUtils;
  *
  * @author Rob Harrop
  * @author Juergen Hoeller
+ * @author Sam Brannen
  * @since 2.0
  */
 @SuppressWarnings("serial")
@@ -59,6 +61,17 @@ public abstract class AttributeAccessorSupport implements AttributeAccessor, Ser
 		return this.attributes.get(name);
 	}
 
+	@Override
+	@SuppressWarnings("unchecked")
+	public <T> T computeAttribute(String name, Function<String, T> computeFunction) {
+		Assert.notNull(name, "Name must not be null");
+		Assert.notNull(computeFunction, "Compute function must not be null");
+		Object value = this.attributes.computeIfAbsent(name, computeFunction);
+		Assert.state(value != null,
+				() -> String.format("Compute function must not return null for attribute named '%s'", name));
+		return (T) value;
+	}
+
 	@Override
 	@Nullable
 	public Object removeAttribute(String name) {

spring-core/src/main/java/org/springframework/core/Conventions.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -225,11 +225,11 @@ public final class Conventions {
 		if (!attributeName.contains("-")) {
 			return attributeName;
 		}
-		char[] chars = attributeName.toCharArray();
-		char[] result = new char[chars.length -1]; // not completely accurate but good guess
+		char[] result = new char[attributeName.length() -1]; // not completely accurate but good guess
 		int currPos = 0;
 		boolean upperCaseNext = false;
-		for (char c : chars) {
+		for (int i = 0; i < attributeName.length(); i++ ) {
+			char c = attributeName.charAt(i);
 			if (c == '-') {
 				upperCaseNext = true;
 			}

spring-core/src/main/java/org/springframework/core/ReactiveAdapterRegistry.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -60,7 +60,28 @@ public class ReactiveAdapterRegistry {
 	@Nullable
 	private static volatile ReactiveAdapterRegistry sharedInstance;
 
-	private final boolean reactorPresent;
+	private static final boolean reactorPresent;
+
+	private static final boolean rxjava1Present;
+
+	private static final boolean rxjava2Present;
+
+	private static final boolean rxjava3Present;
+
+	private static final boolean flowPublisherPresent;
+
+	private static final boolean kotlinCoroutinesPresent;
+
+	static {
+		ClassLoader classLoader = ReactiveAdapterRegistry.class.getClassLoader();
+		reactorPresent = ClassUtils.isPresent("reactor.core.publisher.Flux", classLoader);
+		rxjava1Present = ClassUtils.isPresent("rx.Observable", classLoader) &&
+				ClassUtils.isPresent("rx.RxReactiveStreams", classLoader);
+		rxjava2Present = ClassUtils.isPresent("io.reactivex.Flowable", classLoader);
+		rxjava3Present = ClassUtils.isPresent("io.reactivex.rxjava3.core.Flowable", classLoader);
+		flowPublisherPresent = ClassUtils.isPresent("java.util.concurrent.Flow.Publisher", classLoader);
+		kotlinCoroutinesPresent = ClassUtils.isPresent("kotlinx.coroutines.reactor.MonoKt", classLoader);
+	}
 
 	private final List<ReactiveAdapter> adapters = new ArrayList<>();
 
@@ -70,41 +91,34 @@ public class ReactiveAdapterRegistry {
 	 * @see #getSharedInstance()
 	 */
 	public ReactiveAdapterRegistry() {
-		ClassLoader classLoader = ReactiveAdapterRegistry.class.getClassLoader();
-
 		// Reactor
-		boolean reactorRegistered = false;
-		if (ClassUtils.isPresent("reactor.core.publisher.Flux", classLoader)) {
+		if (reactorPresent) {
 			new ReactorRegistrar().registerAdapters(this);
-			reactorRegistered = true;
 		}
-		this.reactorPresent = reactorRegistered;
 
 		// RxJava1 (deprecated)
-		if (ClassUtils.isPresent("rx.Observable", classLoader) &&
-				ClassUtils.isPresent("rx.RxReactiveStreams", classLoader)) {
+		if (rxjava1Present) {
 			new RxJava1Registrar().registerAdapters(this);
 		}
 
 		// RxJava2
-		if (ClassUtils.isPresent("io.reactivex.Flowable", classLoader)) {
+		if (rxjava2Present) {
 			new RxJava2Registrar().registerAdapters(this);
 		}
-
 		// RxJava3
-		if (ClassUtils.isPresent("io.reactivex.rxjava3.core.Flowable", classLoader)) {
+		if (rxjava3Present) {
 			new RxJava3Registrar().registerAdapters(this);
 		}
 
 		// Java 9+ Flow.Publisher
-		if (ClassUtils.isPresent("java.util.concurrent.Flow.Publisher", classLoader)) {
+		if (flowPublisherPresent) {
 			new ReactorJdkFlowAdapterRegistrar().registerAdapter(this);
 		}
 		// If not present, do nothing for the time being...
 		// We can fall back on "reactive-streams-flow-bridge" (once released)
 
-		// Coroutines
-		if (this.reactorPresent && ClassUtils.isPresent("kotlinx.coroutines.reactor.MonoKt", classLoader)) {
+		// Kotlin Coroutines
+		if (reactorPresent && kotlinCoroutinesPresent) {
 			new CoroutinesRegistrar().registerAdapters(this);
 		}
 	}
@@ -125,7 +139,7 @@ public class ReactiveAdapterRegistry {
 	public void registerReactiveType(ReactiveTypeDescriptor descriptor,
 			Function<Object, Publisher<?>> toAdapter, Function<Publisher<?>, Object> fromAdapter) {
 
-		if (this.reactorPresent) {
+		if (reactorPresent) {
 			this.adapters.add(new ReactorAdapter(descriptor, toAdapter, fromAdapter));
 		}
 		else {

spring-core/src/main/java/org/springframework/core/SpringProperties.java

@@ -21,9 +21,6 @@ import java.io.InputStream;
 import java.net.URL;
 import java.util.Properties;
 
-import org.apache.commons.logging.Log;
-import org.apache.commons.logging.LogFactory;
-
 import org.springframework.lang.Nullable;
 
 /**
@@ -50,8 +47,6 @@ public final class SpringProperties {
 
 	private static final String PROPERTIES_RESOURCE_LOCATION = "spring.properties";
 
-	private static final Log logger = LogFactory.getLog(SpringProperties.class);
-
 	private static final Properties localProperties = new Properties();
 
 
@@ -61,16 +56,13 @@ public final class SpringProperties {
 			URL url = (cl != null ? cl.getResource(PROPERTIES_RESOURCE_LOCATION) :
 					ClassLoader.getSystemResource(PROPERTIES_RESOURCE_LOCATION));
 			if (url != null) {
-				logger.debug("Found 'spring.properties' file in local classpath");
 				try (InputStream is = url.openStream()) {
 					localProperties.load(is);
 				}
 			}
 		}
 		catch (IOException ex) {
-			if (logger.isInfoEnabled()) {
-				logger.info("Could not load 'spring.properties' file from local classpath: " + ex);
-			}
+			System.err.println("Could not load 'spring.properties' file from local classpath: " + ex);
 		}
 	}
 
@@ -108,9 +100,7 @@ public final class SpringProperties {
 				value = System.getProperty(key);
 			}
 			catch (Throwable ex) {
-				if (logger.isDebugEnabled()) {
-					logger.debug("Could not retrieve system property '" + key + "': " + ex);
-				}
+				System.err.println("Could not retrieve system property '" + key + "': " + ex);
 			}
 		}
 		return value;

spring-core/src/main/java/org/springframework/core/codec/Hints.java

@@ -21,6 +21,8 @@ import java.util.Map;
 
 import org.apache.commons.logging.Log;
 
+import org.springframework.core.io.buffer.DataBuffer;
+import org.springframework.core.io.buffer.DataBufferUtils;
 import org.springframework.lang.Nullable;
 import org.springframework.util.CollectionUtils;
 
@@ -148,4 +150,22 @@ public abstract class Hints {
 		}
 	}
 
+	/**
+	 * If the hints contain a {@link #LOG_PREFIX_HINT} and the given logger has
+	 * DEBUG level enabled, apply the log prefix as a hint to the given buffer
+	 * via {@link DataBufferUtils#touch(DataBuffer, Object)}.
+	 * @param buffer the buffer to touch
+	 * @param hints the hints map to check for a log prefix
+	 * @param logger the logger whose level to check
+	 * @since 5.3.2
+	 */
+	public static void touchDataBuffer(DataBuffer buffer, @Nullable Map<String, Object> hints, Log logger) {
+		if (logger.isDebugEnabled() && hints != null) {
+			Object logPrefix = hints.get(LOG_PREFIX_HINT);
+			if (logPrefix != null) {
+				DataBufferUtils.touch(buffer, logPrefix);
+			}
+		}
+	}
+
 }

spring-core/src/main/java/org/springframework/core/codec/ResourceRegionEncoder.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -130,6 +130,9 @@ public class ResourceRegionEncoder extends AbstractEncoder<ResourceRegion> {
 		}
 
 		Flux<DataBuffer> in = DataBufferUtils.read(resource, position, bufferFactory, this.bufferSize);
+		if (logger.isDebugEnabled()) {
+			in = in.doOnNext(buffer -> Hints.touchDataBuffer(buffer, hints, logger));
+		}
 		return DataBufferUtils.takeUntilByteCount(in, count);
 	}
 

spring-core/src/main/java/org/springframework/core/convert/support/GenericConversionService.java

@@ -17,17 +17,17 @@
 package org.springframework.core.convert.support;
 
 import java.lang.reflect.Array;
-import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Deque;
 import java.util.HashSet;
-import java.util.LinkedHashMap;
-import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentLinkedDeque;
+import java.util.concurrent.CopyOnWriteArraySet;
 
 import org.springframework.core.DecoratingProxy;
 import org.springframework.core.ResolvableType;
@@ -500,9 +500,9 @@ public class GenericConversionService implements ConfigurableConversionService {
 	 */
 	private static class Converters {
 
-		private final Set<GenericConverter> globalConverters = new LinkedHashSet<>();
+		private final Set<GenericConverter> globalConverters = new CopyOnWriteArraySet<>();
 
-		private final Map<ConvertiblePair, ConvertersForPair> converters = new LinkedHashMap<>(36);
+		private final Map<ConvertiblePair, ConvertersForPair> converters = new ConcurrentHashMap<>(256);
 
 		public void add(GenericConverter converter) {
 			Set<ConvertiblePair> convertibleTypes = converter.getConvertibleTypes();
@@ -513,8 +513,7 @@ public class GenericConversionService implements ConfigurableConversionService {
 			}
 			else {
 				for (ConvertiblePair convertiblePair : convertibleTypes) {
-					ConvertersForPair convertersForPair = getMatchableConverters(convertiblePair);
-					convertersForPair.add(converter);
+					getMatchableConverters(convertiblePair).add(converter);
 				}
 			}
 		}
@@ -652,7 +651,7 @@ public class GenericConversionService implements ConfigurableConversionService {
 	 */
 	private static class ConvertersForPair {
 
-		private final Deque<GenericConverter> converters = new ArrayDeque<>(1);
+		private final Deque<GenericConverter> converters = new ConcurrentLinkedDeque<>();
 
 		public void add(GenericConverter converter) {
 			this.converters.addFirst(converter);

spring-core/src/main/java/org/springframework/core/io/buffer/DataBufferUtils.java

@@ -487,6 +487,24 @@ public abstract class DataBufferUtils {
 		}
 	}
 
+	/**
+	 * Associate the given hint with the data buffer if it is a pooled buffer
+	 * and supports leak tracking.
+	 * @param dataBuffer the data buffer to attach the hint to
+	 * @param hint the hint to attach
+	 * @return the input buffer
+	 * @since 5.3.2
+	 */
+	@SuppressWarnings("unchecked")
+	public static <T extends DataBuffer> T touch(T dataBuffer, Object hint) {
+		if (dataBuffer instanceof PooledDataBuffer) {
+			return (T) ((PooledDataBuffer) dataBuffer).touch(hint);
+		}
+		else {
+			return dataBuffer;
+		}
+	}
+
 	/**
 	 * Release the given data buffer, if it is a {@link PooledDataBuffer} and
 	 * has been {@linkplain PooledDataBuffer#isAllocated() allocated}.

spring-core/src/main/java/org/springframework/core/io/buffer/LimitedDataBufferList.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -54,11 +54,8 @@ public class LimitedDataBufferList extends ArrayList<DataBuffer> {
 
 	@Override
 	public boolean add(DataBuffer buffer) {
-		boolean result = super.add(buffer);
-		if (result) {
-			updateCount(buffer.readableByteCount());
-		}
-		return result;
+		updateCount(buffer.readableByteCount());
+		return super.add(buffer);
 	}
 
 	@Override

spring-core/src/main/java/org/springframework/core/io/buffer/NettyDataBuffer.java

@@ -315,6 +315,12 @@ public class NettyDataBuffer implements PooledDataBuffer {
 		return new NettyDataBuffer(this.byteBuf.retain(), this.dataBufferFactory);
 	}
 
+	@Override
+	public PooledDataBuffer touch(Object hint) {
+		this.byteBuf.touch(hint);
+		return this;
+	}
+
 	@Override
 	public boolean release() {
 		return this.byteBuf.release();

spring-core/src/main/java/org/springframework/core/io/buffer/PooledDataBuffer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -38,6 +38,13 @@ public interface PooledDataBuffer extends DataBuffer {
 	 */
 	PooledDataBuffer retain();
 
+	/**
+	 * Associate the given hint with the data buffer for debugging purposes.
+	 * @return this buffer
+	 * @since 5.3.2
+	 */
+	PooledDataBuffer touch(Object hint);
+
 	/**
 	 * Decrease the reference count for this buffer by one,
 	 * and deallocate it once the count reaches zero.

spring-core/src/main/java/org/springframework/core/io/support/PathMatchingResourcePatternResolver.java

@@ -432,6 +432,9 @@ public class PathMatchingResourcePatternResolver implements ResourcePatternResol
 						// Possibly "c:" drive prefix on Windows, to be upper-cased for proper duplicate detection
 						filePath = StringUtils.capitalize(filePath);
 					}
+					// # can appear in directories/filenames, java.net.URL should not treat it as a fragment
+					filePath = StringUtils.replace(filePath, "#", "%23");
+					// Build URL that points to the root of the jar file
 					UrlResource jarResource = new UrlResource(ResourceUtils.JAR_URL_PREFIX +
 							ResourceUtils.FILE_URL_PREFIX + filePath + ResourceUtils.JAR_URL_SEPARATOR);
 					// Potentially overlapping with URLClassLoader.getURLs() result above!

spring-core/src/main/java/org/springframework/core/io/support/ResourceArrayPropertyEditor.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -18,10 +18,11 @@ package org.springframework.core.io.support;
 
 import java.beans.PropertyEditorSupport;
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
-import java.util.List;
+import java.util.Collections;
+import java.util.LinkedHashSet;
+import java.util.Set;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
@@ -129,7 +130,7 @@ public class ResourceArrayPropertyEditor extends PropertyEditorSupport {
 	public void setValue(Object value) throws IllegalArgumentException {
 		if (value instanceof Collection || (value instanceof Object[] && !(value instanceof Resource[]))) {
 			Collection<?> input = (value instanceof Collection ? (Collection<?>) value : Arrays.asList((Object[]) value));
-			List<Resource> merged = new ArrayList<>();
+			Set<Resource> merged = new LinkedHashSet<>();
 			for (Object element : input) {
 				if (element instanceof String) {
 					// A location pattern: resolve it into a Resource array.
@@ -137,11 +138,7 @@ public class ResourceArrayPropertyEditor extends PropertyEditorSupport {
 					String pattern = resolvePath((String) element).trim();
 					try {
 						Resource[] resources = this.resourcePatternResolver.getResources(pattern);
-						for (Resource resource : resources) {
-							if (!merged.contains(resource)) {
-								merged.add(resource);
-							}
-						}
+						Collections.addAll(merged, resources);
 					}
 					catch (IOException ex) {
 						// ignore - might be an unresolved placeholder or non-existing base directory
@@ -152,10 +149,7 @@ public class ResourceArrayPropertyEditor extends PropertyEditorSupport {
 				}
 				else if (element instanceof Resource) {
 					// A Resource object: add it to the result.
-					Resource resource = (Resource) element;
-					if (!merged.contains(resource)) {
-						merged.add(resource);
-					}
+					merged.add((Resource) element);
 				}
 				else {
 					throw new IllegalArgumentException("Cannot convert element [" + element + "] to [" +

spring-core/src/main/java/org/springframework/util/AntPathMatcher.java

@@ -644,7 +644,7 @@ public class AntPathMatcher implements PathMatcher {
 
 		private static final Pattern GLOB_PATTERN = Pattern.compile("\\?|\\*|\\{((?:\\{[^/]+?}|[^/{}]|\\\\[{}])+?)}");
 
-		private static final String DEFAULT_VARIABLE_PATTERN = "(.*)";
+		private static final String DEFAULT_VARIABLE_PATTERN = "((?s).*)";
 
 		private final String rawPattern;
 

spring-core/src/main/java/org/springframework/util/MimeType.java

@@ -16,6 +16,8 @@
 
 package org.springframework.util;
 
+import java.io.IOException;
+import java.io.ObjectInputStream;
 import java.io.Serializable;
 import java.nio.charset.Charset;
 import java.util.BitSet;
@@ -104,7 +106,7 @@ public class MimeType implements Comparable<MimeType>, Serializable {
 	private final Map<String, String> parameters;
 
 	@Nullable
-	private Charset resolvedCharset;
+	private transient Charset resolvedCharset;
 
 	@Nullable
 	private volatile String toStringValue;
@@ -184,9 +186,9 @@ public class MimeType implements Comparable<MimeType>, Serializable {
 		this.subtype = subtype.toLowerCase(Locale.ENGLISH);
 		if (!CollectionUtils.isEmpty(parameters)) {
 			Map<String, String> map = new LinkedCaseInsensitiveMap<>(parameters.size(), Locale.ENGLISH);
-			parameters.forEach((attribute, value) -> {
-				checkParameters(attribute, value);
-				map.put(attribute, value);
+			parameters.forEach((parameter, value) -> {
+				checkParameters(parameter, value);
+				map.put(parameter, value);
 			});
 			this.parameters = Collections.unmodifiableMap(map);
 		}
@@ -224,11 +226,11 @@ public class MimeType implements Comparable<MimeType>, Serializable {
 		}
 	}
 
-	protected void checkParameters(String attribute, String value) {
-		Assert.hasLength(attribute, "'attribute' must not be empty");
+	protected void checkParameters(String parameter, String value) {
+		Assert.hasLength(parameter, "'parameter' must not be empty");
 		Assert.hasLength(value, "'value' must not be empty");
-		checkToken(attribute);
-		if (PARAM_CHARSET.equals(attribute)) {
+		checkToken(parameter);
+		if (PARAM_CHARSET.equals(parameter)) {
 			if (this.resolvedCharset == null) {
 				this.resolvedCharset = Charset.forName(unquote(value));
 			}
@@ -591,6 +593,17 @@ public class MimeType implements Comparable<MimeType>, Serializable {
 		return 0;
 	}
 
+	private void readObject(ObjectInputStream ois) throws IOException, ClassNotFoundException {
+		// Rely on default serialization, just initialize state after deserialization.
+		ois.defaultReadObject();
+
+		// Initialize transient fields.
+		String charsetName = getParameter(PARAM_CHARSET);
+		if (charsetName != null) {
+			this.resolvedCharset = Charset.forName(unquote(charsetName));
+		}
+	}
+
 
 	/**
 	 * Parse the given String value into a {@code MimeType} object,

spring-core/src/main/java/org/springframework/util/ReflectionUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -824,6 +824,19 @@ public abstract class ReflectionUtils {
 		 * @param method the method to check
 		 */
 		boolean matches(Method method);
+
+		/**
+		 * Create a composite filter based on this filter <em>and</em> the provided filter.
+		 * <p>If this filter does not match, the next filter will not be applied.
+		 * @param next the next {@code MethodFilter}
+		 * @return a composite {@code MethodFilter}
+		 * @throws IllegalArgumentException if the MethodFilter argument is {@code null}
+		 * @since 5.3.2
+		 */
+		default MethodFilter and(MethodFilter next) {
+			Assert.notNull(next, "Next MethodFilter must not be null");
+			return method -> matches(method) && next.matches(method);
+		}
 	}
 
 
@@ -852,6 +865,19 @@ public abstract class ReflectionUtils {
 		 * @param field the field to check
 		 */
 		boolean matches(Field field);
+
+		/**
+		 * Create a composite filter based on this filter <em>and</em> the provided filter.
+		 * <p>If this filter does not match, the next filter will not be applied.
+		 * @param next the next {@code FieldFilter}
+		 * @return a composite {@code FieldFilter}
+		 * @throws IllegalArgumentException if the FieldFilter argument is {@code null}
+		 * @since 5.3.2
+		 */
+		default FieldFilter and(FieldFilter next) {
+			Assert.notNull(next, "Next FieldFilter must not be null");
+			return field -> matches(field) && next.matches(field);
+		}
 	}
 
 }

spring-core/src/main/java/org/springframework/util/xml/XMLEventStreamWriter.java

@@ -161,9 +161,8 @@ class XMLEventStreamWriter implements XMLStreamWriter {
 	public void writeEndElement() throws XMLStreamException {
 		closeEmptyElementIfNecessary();
 		int last = this.endElements.size() - 1;
-		EndElement lastEndElement = this.endElements.get(last);
+		EndElement lastEndElement = this.endElements.remove(last);
 		this.eventWriter.add(lastEndElement);
-		this.endElements.remove(last);
 	}
 
 	@Override

spring-core/src/test/java/org/springframework/core/AttributeAccessorSupportTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,39 +17,61 @@
 package org.springframework.core;
 
 import java.util.Arrays;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.function.Function;
 
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
 
 /**
+ * Unit tests for {@link AttributeAccessorSupport}.
+ *
  * @author Rob Harrop
  * @author Sam Brannen
  * @since 2.0
  */
 class AttributeAccessorSupportTests {
 
-	private static final String NAME = "foo";
+	private static final String NAME = "name";
 
-	private static final String VALUE = "bar";
+	private static final String VALUE = "value";
+
+	private final AttributeAccessor attributeAccessor = new SimpleAttributeAccessorSupport();
 
-	private AttributeAccessor attributeAccessor = new SimpleAttributeAccessorSupport();
 
 	@Test
-	void setAndGet() throws Exception {
+	void setAndGet() {
 		this.attributeAccessor.setAttribute(NAME, VALUE);
 		assertThat(this.attributeAccessor.getAttribute(NAME)).isEqualTo(VALUE);
 	}
 
 	@Test
-	void setAndHas() throws Exception {
+	void setAndHas() {
 		assertThat(this.attributeAccessor.hasAttribute(NAME)).isFalse();
 		this.attributeAccessor.setAttribute(NAME, VALUE);
 		assertThat(this.attributeAccessor.hasAttribute(NAME)).isTrue();
 	}
 
 	@Test
-	void remove() throws Exception {
+	void computeAttribute() {
+		AtomicInteger atomicInteger = new AtomicInteger();
+		Function<String, String> computeFunction = name -> "computed-" + atomicInteger.incrementAndGet();
+
+		assertThat(this.attributeAccessor.hasAttribute(NAME)).isFalse();
+		this.attributeAccessor.computeAttribute(NAME, computeFunction);
+		assertThat(this.attributeAccessor.getAttribute(NAME)).isEqualTo("computed-1");
+		this.attributeAccessor.computeAttribute(NAME, computeFunction);
+		assertThat(this.attributeAccessor.getAttribute(NAME)).isEqualTo("computed-1");
+
+		this.attributeAccessor.removeAttribute(NAME);
+		assertThat(this.attributeAccessor.hasAttribute(NAME)).isFalse();
+		this.attributeAccessor.computeAttribute(NAME, computeFunction);
+		assertThat(this.attributeAccessor.getAttribute(NAME)).isEqualTo("computed-2");
+	}
+
+	@Test
+	void remove() {
 		assertThat(this.attributeAccessor.hasAttribute(NAME)).isFalse();
 		this.attributeAccessor.setAttribute(NAME, VALUE);
 		assertThat(this.attributeAccessor.removeAttribute(NAME)).isEqualTo(VALUE);
@@ -57,13 +79,13 @@ class AttributeAccessorSupportTests {
 	}
 
 	@Test
-	void attributeNames() throws Exception {
+	void attributeNames() {
 		this.attributeAccessor.setAttribute(NAME, VALUE);
 		this.attributeAccessor.setAttribute("abc", "123");
 		String[] attributeNames = this.attributeAccessor.attributeNames();
 		Arrays.sort(attributeNames);
-		assertThat(Arrays.binarySearch(attributeNames, NAME) > -1).isTrue();
-		assertThat(Arrays.binarySearch(attributeNames, "abc") > -1).isTrue();
+		assertThat(Arrays.binarySearch(attributeNames, "abc")).isEqualTo(0);
+		assertThat(Arrays.binarySearch(attributeNames, NAME)).isEqualTo(1);
 	}
 
 	@SuppressWarnings("serial")

spring-core/src/test/java/org/springframework/core/ReactiveAdapterRegistryTests.java

@@ -367,8 +367,9 @@ class ReactiveAdapterRegistryTests {
 	private static class ExtendedFlux<T> extends Flux<T> {
 
 		@Override
-		public void subscribe(CoreSubscriber actual) {
+		public void subscribe(CoreSubscriber<? super T> actual) {
 			throw new UnsupportedOperationException();
 		}
 	}
+
 }

spring-core/src/test/java/org/springframework/core/io/buffer/DataBufferUtilsTests.java

@@ -35,6 +35,8 @@ import java.util.List;
 import java.util.concurrent.CountDownLatch;
 
 import io.netty.buffer.ByteBuf;
+import io.netty.buffer.PooledByteBufAllocator;
+import org.junit.jupiter.api.Test;
 import org.mockito.stubbing.Answer;
 import org.reactivestreams.Subscription;
 import reactor.core.publisher.BaseSubscriber;
@@ -834,6 +836,22 @@ class DataBufferUtilsTests extends AbstractDataBufferAllocatingTests {
 				.verifyError(DataBufferLimitException.class);
 	}
 
+	@Test // gh-26060
+	void joinWithLimitDoesNotOverRelease() {
+		NettyDataBufferFactory bufferFactory = new NettyDataBufferFactory(PooledByteBufAllocator.DEFAULT);
+		byte[] bytes = "foo-bar-baz".getBytes(StandardCharsets.UTF_8);
+
+		NettyDataBuffer buffer = bufferFactory.allocateBuffer(bytes.length);
+		buffer.getNativeBuffer().retain(); // should be at 2 now
+		buffer.write(bytes);
+
+		Mono<DataBuffer> result = DataBufferUtils.join(Flux.just(buffer), 8);
+
+		StepVerifier.create(result).verifyError(DataBufferLimitException.class);
+		assertThat(buffer.getNativeBuffer().refCnt()).isEqualTo(1);
+		buffer.release();
+	}
+
 	@ParameterizedDataBufferAllocatingTest
 	void joinErrors(String displayName, DataBufferFactory bufferFactory) {
 		super.bufferFactory = bufferFactory;

spring-core/src/test/java/org/springframework/core/io/buffer/LimitedDataBufferListTests.java

@@ -17,9 +17,11 @@ package org.springframework.core.io.buffer;
 
 import java.nio.charset.StandardCharsets;
 
-import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
 /**
  * Unit tests for {@link LimitedDataBufferList}.
  * @author Rossen Stoyanchev
@@ -29,8 +31,10 @@ public class LimitedDataBufferListTests {
 
 	@Test
 	void limitEnforced() {
-		Assertions.assertThatThrownBy(() -> new LimitedDataBufferList(5).add(toDataBuffer("123456")))
-				.isInstanceOf(DataBufferLimitException.class);
+		LimitedDataBufferList list = new LimitedDataBufferList(5);
+
+		assertThatThrownBy(() -> list.add(toDataBuffer("123456"))).isInstanceOf(DataBufferLimitException.class);
+		assertThat(list).isEmpty();
 	}
 
 	@Test

spring-core/src/test/java/org/springframework/util/AntPathMatcherTests.java

@@ -130,6 +130,7 @@ class AntPathMatcherTests {
 		assertThat(pathMatcher.match("", "")).isTrue();
 
 		assertThat(pathMatcher.match("/{bla}.*", "/testing.html")).isTrue();
+		assertThat(pathMatcher.match("/{bla}", "//x\ny")).isTrue();
 	}
 
 	@Test

spring-core/src/test/java/org/springframework/util/MimeTypeTests.java

@@ -26,6 +26,7 @@ import org.junit.jupiter.api.Test;
 
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.support.DefaultConversionService;
+import org.springframework.core.testfixture.io.SerializationTestUtils;
 
 import static java.util.Collections.singletonMap;
 import static org.assertj.core.api.Assertions.assertThat;
@@ -267,13 +268,13 @@ class MimeTypeTests {
 		assertThat(mimeType.getParameter("attr")).isEqualTo("'v>alue'");
 	}
 
-	@Test // SPR-16630
+	@Test  // SPR-16630
 	void parseMimeTypeWithSpacesAroundEquals() {
 		MimeType mimeType = MimeTypeUtils.parseMimeType("multipart/x-mixed-replace;boundary = --myboundary");
 		assertThat(mimeType.getParameter("boundary")).isEqualTo("--myboundary");
 	}
 
-	@Test // SPR-16630
+	@Test  // SPR-16630
 	void parseMimeTypeWithSpacesAroundEqualsAndQuotedValue() {
 		MimeType mimeType = MimeTypeUtils.parseMimeType("text/plain; foo = \" bar \" ");
 		assertThat(mimeType.getParameter("foo")).isEqualTo("\" bar \"");
@@ -303,14 +304,14 @@ class MimeTypeTests {
 		assertThat(mimeTypes.size()).as("Invalid amount of mime types").isEqualTo(0);
 	}
 
-	@Test // gh-23241
+	@Test  // gh-23241
 	void parseMimeTypesWithTrailingComma() {
 		List<MimeType> mimeTypes = MimeTypeUtils.parseMimeTypes("text/plain, text/html,");
 		assertThat(mimeTypes).as("No mime types returned").isNotNull();
 		assertThat(mimeTypes.size()).as("Incorrect number of mime types").isEqualTo(2);
 	}
 
-	@Test // SPR-17459
+	@Test  // SPR-17459
 	void parseMimeTypesWithQuotedParameters() {
 		testWithQuotedParameters("foo/bar;param=\",\"");
 		testWithQuotedParameters("foo/bar;param=\"s,a,\"");
@@ -332,7 +333,7 @@ class MimeTypeTests {
 		assertThat(type.getSubtypeSuffix()).isEqualTo("json");
 	}
 
-	@Test // gh-25350
+	@Test  // gh-25350
 	void wildcardSubtypeCompatibleWithSuffix() {
 		MimeType applicationStar = new MimeType("application", "*");
 		MimeType applicationVndJson = new MimeType("application", "vnd.something+json");
@@ -342,8 +343,9 @@ class MimeTypeTests {
 	private void testWithQuotedParameters(String... mimeTypes) {
 		String s = String.join(",", mimeTypes);
 		List<MimeType> actual = MimeTypeUtils.parseMimeTypes(s);
+
 		assertThat(actual.size()).isEqualTo(mimeTypes.length);
-		for (int i=0; i < mimeTypes.length; i++) {
+		for (int i = 0; i < mimeTypes.length; i++) {
 			assertThat(actual.get(i).toString()).isEqualTo(mimeTypes[i]);
 		}
 	}
@@ -370,6 +372,7 @@ class MimeTypeTests {
 
 		List<MimeType> result = new ArrayList<>(expected);
 		Random rnd = new Random();
+
 		// shuffle & sort 10 times
 		for (int i = 0; i < 10; i++) {
 			Collections.shuffle(result, rnd);
@@ -399,11 +402,7 @@ class MimeTypeTests {
 		assertThat(m2.compareTo(m1) != 0).as("Invalid comparison result").isTrue();
 	}
 
-	/**
-	 * SPR-13157
-	 * @since 4.2
-	 */
-	@Test
+	@Test  // SPR-13157
 	void equalsIsCaseInsensitiveForCharsets() {
 		MimeType m1 = new MimeType("text", "plain", singletonMap("charset", "UTF-8"));
 		MimeType m2 = new MimeType("text", "plain", singletonMap("charset", "utf-8"));
@@ -413,4 +412,12 @@ class MimeTypeTests {
 		assertThat(m2.compareTo(m1)).isEqualTo(0);
 	}
 
+	@Test  // gh-26127
+	void serialize() throws Exception {
+		MimeType original = new MimeType("text", "plain", StandardCharsets.UTF_8);
+		MimeType deserialized = SerializationTestUtils.serializeAndDeserialize(original);
+		assertThat(deserialized).isEqualTo(original);
+		assertThat(original).isEqualTo(deserialized);
+	}
+
 }

spring-core/src/test/java/org/springframework/util/ReflectionUtilsTests.java

@@ -186,12 +186,7 @@ class ReflectionUtilsTests {
 	@Test
 	void doWithProtectedMethods() {
 		ListSavingMethodCallback mc = new ListSavingMethodCallback();
-		ReflectionUtils.doWithMethods(TestObject.class, mc, new ReflectionUtils.MethodFilter() {
-			@Override
-			public boolean matches(Method m) {
-				return Modifier.isProtected(m.getModifiers());
-			}
-		});
+		ReflectionUtils.doWithMethods(TestObject.class, mc, method -> Modifier.isProtected(method.getModifiers()));
 		assertThat(mc.getMethodNames().isEmpty()).isFalse();
 		assertThat(mc.getMethodNames().contains("clone")).as("Must find protected method on Object").isTrue();
 		assertThat(mc.getMethodNames().contains("finalize")).as("Must find protected method on Object").isTrue();

spring-core/src/testFixtures/java/org/springframework/core/testfixture/io/buffer/LeakAwareDataBuffer.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@
 package org.springframework.core.testfixture.io.buffer;
 
 import org.springframework.core.io.buffer.DataBuffer;
+import org.springframework.core.io.buffer.DataBufferUtils;
 import org.springframework.core.io.buffer.DataBufferWrapper;
 import org.springframework.core.io.buffer.PooledDataBuffer;
 import org.springframework.util.Assert;
@@ -67,19 +68,19 @@ class LeakAwareDataBuffer extends DataBufferWrapper implements PooledDataBuffer
 
 	@Override
 	public PooledDataBuffer retain() {
-		DataBuffer delegate = dataBuffer();
-		if (delegate instanceof PooledDataBuffer) {
-			((PooledDataBuffer) delegate).retain();
-		}
+		DataBufferUtils.retain(dataBuffer());
+		return this;
+	}
+
+	@Override
+	public PooledDataBuffer touch(Object hint) {
+		DataBufferUtils.touch(dataBuffer(), hint);
 		return this;
 	}
 
 	@Override
 	public boolean release() {
-		DataBuffer delegate = dataBuffer();
-		if (delegate instanceof PooledDataBuffer) {
-			((PooledDataBuffer) delegate).release();
-		}
+		DataBufferUtils.release(dataBuffer());
 		return isAllocated();
 	}
 

spring-expression/src/main/java/org/springframework/expression/spel/ast/AstUtils.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -54,10 +54,9 @@ public abstract class AstUtils {
 			}
 			else {
 				if (targetType != null) {
-					int pos = 0;
 					for (Class<?> clazz : targets) {
 						if (clazz == targetType) {  // put exact matches on the front to be tried first?
-							specificAccessors.add(pos++, resolver);
+							specificAccessors.add(resolver);
 						}
 						else if (clazz.isAssignableFrom(targetType)) {  // put supertype matches at the end of the
 							// specificAccessor list

spring-expression/src/main/java/org/springframework/expression/spel/support/ReflectivePropertyAccessor.java

@@ -47,7 +47,7 @@ import org.springframework.util.StringUtils;
 
 /**
  * A powerful {@link PropertyAccessor} that uses reflection to access properties
- * for reading and possibly also for writing.
+ * for reading and possibly also for writing on a target instance.
  *
  * <p>A property can be referenced through a public getter method (when being read)
  * or a public setter method (when being written), and also as a public field.
@@ -98,8 +98,8 @@ public class ReflectivePropertyAccessor implements PropertyAccessor {
 	}
 
 	/**
-	 * Create a new property accessor for reading and possibly writing.
-	 * @param allowWrite whether to also allow for write operations
+	 * Create a new property accessor for reading and possibly also writing.
+	 * @param allowWrite whether to allow write operations on a target instance
 	 * @since 4.3.15
 	 * @see #canWrite
 	 */
@@ -628,8 +628,8 @@ public class ReflectivePropertyAccessor implements PropertyAccessor {
 
 		@Override
 		public String toString() {
-			return "CacheKey [clazz=" + this.clazz.getName() + ", property=" + this.property + ", " +
-					this.property + ", targetIsClass=" + this.targetIsClass + "]";
+			return "PropertyCacheKey [clazz=" + this.clazz.getName() + ", property=" + this.property +
+					", targetIsClass=" + this.targetIsClass + "]";
 		}
 
 		@Override

spring-expression/src/test/java/org/springframework/expression/spel/standard/SpelParserTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -36,10 +36,10 @@ import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
  * @author Andy Clement
  * @author Juergen Hoeller
  */
-public class SpelParserTests {
+class SpelParserTests {
 
 	@Test
-	public void theMostBasic() {
+	void theMostBasic() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("2");
 		assertThat(expr).isNotNull();
@@ -50,7 +50,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void valueType() {
+	void valueType() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		EvaluationContext ctx = new StandardEvaluationContext();
 		Class<?> c = parser.parseRaw("2").getValueType();
@@ -66,7 +66,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void whitespace() {
+	void whitespace() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("2      +    3");
 		assertThat(expr.getValue()).isEqualTo(5);
@@ -79,7 +79,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void arithmeticPlus1() {
+	void arithmeticPlus1() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("2+2");
 		assertThat(expr).isNotNull();
@@ -88,66 +88,65 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void arithmeticPlus2() {
+	void arithmeticPlus2() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("37+41");
 		assertThat(expr.getValue()).isEqualTo(78);
 	}
 
 	@Test
-	public void arithmeticMultiply1() {
+	void arithmeticMultiply1() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("2*3");
 		assertThat(expr).isNotNull();
 		assertThat(expr.getAST()).isNotNull();
-		// printAst(expr.getAST(),0);
 		assertThat(expr.getValue()).isEqualTo(6);
 	}
 
 	@Test
-	public void arithmeticPrecedence1() {
+	void arithmeticPrecedence1() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("2*3+5");
 		assertThat(expr.getValue()).isEqualTo(11);
 	}
 
 	@Test
-	public void generalExpressions() {
+	void generalExpressions() {
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> {
 			SpelExpressionParser parser = new SpelExpressionParser();
 			parser.parseRaw("new String");
 		})
-		.satisfies(ex -> parseExceptionRequirements(SpelMessage.MISSING_CONSTRUCTOR_ARGS, 10));
+		.satisfies(parseExceptionRequirements(SpelMessage.MISSING_CONSTRUCTOR_ARGS, 10));
 
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> {
 			SpelExpressionParser parser = new SpelExpressionParser();
 			parser.parseRaw("new String(3,");
 		})
-		.satisfies(ex -> parseExceptionRequirements(SpelMessage.RUN_OUT_OF_ARGUMENTS, 10));
+		.satisfies(parseExceptionRequirements(SpelMessage.RUN_OUT_OF_ARGUMENTS, 10));
 
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> {
 			SpelExpressionParser parser = new SpelExpressionParser();
 			parser.parseRaw("new String(3");
 		})
-		.satisfies(ex -> parseExceptionRequirements(SpelMessage.RUN_OUT_OF_ARGUMENTS, 10));
+		.satisfies(parseExceptionRequirements(SpelMessage.RUN_OUT_OF_ARGUMENTS, 10));
 
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> {
 			SpelExpressionParser parser = new SpelExpressionParser();
 			parser.parseRaw("new String(");
 		})
-		.satisfies(ex -> parseExceptionRequirements(SpelMessage.RUN_OUT_OF_ARGUMENTS, 10));
+		.satisfies(parseExceptionRequirements(SpelMessage.RUN_OUT_OF_ARGUMENTS, 10));
 
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> {
 			SpelExpressionParser parser = new SpelExpressionParser();
 			parser.parseRaw("\"abc");
 		})
-		.satisfies(ex -> parseExceptionRequirements(SpelMessage.NON_TERMINATING_DOUBLE_QUOTED_STRING, 0));
+		.satisfies(parseExceptionRequirements(SpelMessage.NON_TERMINATING_DOUBLE_QUOTED_STRING, 0));
 
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> {
 			SpelExpressionParser parser = new SpelExpressionParser();
 			parser.parseRaw("'abc");
 		})
-		.satisfies(ex -> parseExceptionRequirements(SpelMessage.NON_TERMINATING_QUOTED_STRING, 0));
+		.satisfies(parseExceptionRequirements(SpelMessage.NON_TERMINATING_QUOTED_STRING, 0));
 
 	}
 
@@ -161,38 +160,38 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void arithmeticPrecedence2() {
+	void arithmeticPrecedence2() {
 		SpelExpressionParser parser = new SpelExpressionParser();
 		SpelExpression expr = parser.parseRaw("2+3*5");
 		assertThat(expr.getValue()).isEqualTo(17);
 	}
 
 	@Test
-	public void arithmeticPrecedence3() {
+	void arithmeticPrecedence3() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("3+10/2");
 		assertThat(expr.getValue()).isEqualTo(8);
 	}
 
 	@Test
-	public void arithmeticPrecedence4() {
+	void arithmeticPrecedence4() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("10/2+3");
 		assertThat(expr.getValue()).isEqualTo(8);
 	}
 
 	@Test
-	public void arithmeticPrecedence5() {
+	void arithmeticPrecedence5() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("(4+10)/2");
 		assertThat(expr.getValue()).isEqualTo(7);
 	}
 
 	@Test
-	public void arithmeticPrecedence6() {
+	void arithmeticPrecedence6() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("(3+2)*2");
 		assertThat(expr.getValue()).isEqualTo(10);
 	}
 
 	@Test
-	public void booleanOperators() {
+	void booleanOperators() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("true");
 		assertThat(expr.getValue(Boolean.class)).isEqualTo(Boolean.TRUE);
 		expr = new SpelExpressionParser().parseRaw("false");
@@ -210,7 +209,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void booleanOperators_symbolic_spr9614() {
+	void booleanOperators_symbolic_spr9614() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("true");
 		assertThat(expr.getValue(Boolean.class)).isEqualTo(Boolean.TRUE);
 		expr = new SpelExpressionParser().parseRaw("false");
@@ -228,7 +227,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void stringLiterals() {
+	void stringLiterals() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("'howdy'");
 		assertThat(expr.getValue()).isEqualTo("howdy");
 		expr = new SpelExpressionParser().parseRaw("'hello '' world'");
@@ -236,13 +235,13 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void stringLiterals2() {
+	void stringLiterals2() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("'howdy'.substring(0,2)");
 		assertThat(expr.getValue()).isEqualTo("ho");
 	}
 
 	@Test
-	public void testStringLiterals_DoubleQuotes_spr9620() {
+	void testStringLiterals_DoubleQuotes_spr9620() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("\"double quote: \"\".\"");
 		assertThat(expr.getValue()).isEqualTo("double quote: \".");
 		expr = new SpelExpressionParser().parseRaw("\"hello \"\" world\"");
@@ -250,7 +249,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void testStringLiterals_DoubleQuotes_spr9620_2() {
+	void testStringLiterals_DoubleQuotes_spr9620_2() {
 		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() ->
 				new SpelExpressionParser().parseRaw("\"double quote: \\\"\\\".\""))
 			.satisfies(ex -> {
@@ -260,7 +259,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void positionalInformation() {
+	void positionalInformation() {
 		SpelExpression expr = new SpelExpressionParser().parseRaw("true and true or false");
 		SpelNode rootAst = expr.getAST();
 		OpOr operatorOr = (OpOr) rootAst;
@@ -289,7 +288,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void tokenKind() {
+	void tokenKind() {
 		TokenKind tk = TokenKind.NOT;
 		assertThat(tk.hasPayload()).isFalse();
 		assertThat(tk.toString()).isEqualTo("NOT(!)");
@@ -304,7 +303,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void token() {
+	void token() {
 		Token token = new Token(TokenKind.NOT, 0, 3);
 		assertThat(token.kind).isEqualTo(TokenKind.NOT);
 		assertThat(token.startPos).isEqualTo(0);
@@ -319,7 +318,7 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void exceptions() {
+	void exceptions() {
 		ExpressionException exprEx = new ExpressionException("test");
 		assertThat(exprEx.getSimpleMessage()).isEqualTo("test");
 		assertThat(exprEx.toDetailedString()).isEqualTo("test");
@@ -337,13 +336,13 @@ public class SpelParserTests {
 	}
 
 	@Test
-	public void parseMethodsOnNumbers() {
+	void parseMethodsOnNumbers() {
 		checkNumber("3.14.toString()", "3.14", String.class);
 		checkNumber("3.toString()", "3", String.class);
 	}
 
 	@Test
-	public void numerics() {
+	void numerics() {
 		checkNumber("2", 2, Integer.class);
 		checkNumber("22", 22, Integer.class);
 		checkNumber("+22", 22, Integer.class);
@@ -385,8 +384,7 @@ public class SpelParserTests {
 
 	private void checkNumberError(String expression, SpelMessage expectedMessage) {
 		SpelExpressionParser parser = new SpelExpressionParser();
-		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() ->
-				parser.parseRaw(expression))
+		assertThatExceptionOfType(SpelParseException.class).isThrownBy(() -> parser.parseRaw(expression))
 			.satisfies(ex -> assertThat(ex.getMessageCode()).isEqualTo(expectedMessage));
 	}
 

spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCreatorFactory.java

@@ -30,7 +30,6 @@ import java.util.Set;
 
 import org.springframework.dao.InvalidDataAccessApiUsageException;
 import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
 
 /**
  * Helper class that efficiently creates multiple {@link PreparedStatementCreator}
@@ -200,9 +199,8 @@ public class PreparedStatementCreatorFactory {
 
 		public PreparedStatementCreatorImpl(String actualSql, List<?> parameters) {
 			this.actualSql = actualSql;
-			Assert.notNull(parameters, "Parameters List must not be null");
 			this.parameters = parameters;
-			if (this.parameters.size() != declaredParameters.size()) {
+			if (parameters.size() != declaredParameters.size()) {
 				// Account for named parameters being used multiple times
 				Set<String> names = new HashSet<>();
 				for (int i = 0; i < parameters.size(); i++) {

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/NamedParameterUtils.java

@@ -345,9 +345,9 @@ public abstract class NamedParameterUtils {
 		for (int i = 0; i < paramNames.size(); i++) {
 			String paramName = paramNames.get(i);
 			try {
-				Object value = paramSource.getValue(paramName);
 				SqlParameter param = findParameter(declaredParams, paramName, i);
-				paramArray[i] = (param != null ? new SqlParameterValue(param, value) : value);
+				paramArray[i] = (param != null ? new SqlParameterValue(param, paramSource.getValue(paramName)) :
+						SqlParameterSourceUtils.getTypedValue(paramSource, paramName));
 			}
 			catch (IllegalArgumentException ex) {
 				throw new InvalidDataAccessApiUsageException(

spring-jdbc/src/main/java/org/springframework/jdbc/core/namedparam/SqlParameterSourceUtils.java

@@ -92,17 +92,13 @@ public abstract class SqlParameterSourceUtils {
 	 * @param source the source of parameter values and type information
 	 * @param parameterName the name of the parameter
 	 * @return the value object
+	 * @see SqlParameterValue
 	 */
 	@Nullable
 	public static Object getTypedValue(SqlParameterSource source, String parameterName) {
 		int sqlType = source.getSqlType(parameterName);
 		if (sqlType != SqlParameterSource.TYPE_UNKNOWN) {
-			if (source.getTypeName(parameterName) != null) {
-				return new SqlParameterValue(sqlType, source.getTypeName(parameterName), source.getValue(parameterName));
-			}
-			else {
-				return new SqlParameterValue(sqlType, source.getValue(parameterName));
-			}
+			return new SqlParameterValue(sqlType, source.getTypeName(parameterName), source.getValue(parameterName));
 		}
 		else {
 			return source.getValue(parameterName);

spring-jdbc/src/main/java/org/springframework/jdbc/core/simple/AbstractJdbcCall.java

@@ -433,7 +433,7 @@ public abstract class AbstractJdbcCall {
 	/**
 	 * Match the provided in parameter values with registered parameters and
 	 * parameters defined via meta-data processing.
-	 * @param parameterSource the parameter vakues provided as a {@link SqlParameterSource}
+	 * @param parameterSource the parameter values provided as a {@link SqlParameterSource}
 	 * @return a Map with parameter names and values
 	 */
 	protected Map<String, Object> matchInParameterValuesWithCallParameters(SqlParameterSource parameterSource) {

spring-jdbc/src/main/kotlin/org/springframework/jdbc/core/JdbcOperationsExtensions.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors
+ * Copyright 2002-2021 the original author or authors
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -54,8 +54,10 @@ inline fun <reified T> JdbcOperations.queryForObject(sql: String, args: Array<ou
  * @author Mario Arias
  * @since 5.0
  */
+@Suppress("DEPRECATION")
+// TODO Replace by the vararg variant in Spring Framework 6
 inline fun <reified T> JdbcOperations.queryForObject(sql: String, args: Array<out Any>): T? =
-		queryForObject(sql, T::class.java, args) as T
+		queryForObject(sql, args, T::class.java) as T
 
 /**
  * Extension for [JdbcOperations.queryForList] providing a `queryForList<Foo>("...")` variant.
@@ -86,8 +88,11 @@ inline fun <reified T> JdbcOperations.queryForList(sql: String, args: Array<out
  * @author Mario Arias
  * @since 5.0
  */
+@Suppress("DEPRECATION")
+// TODO Replace by the vararg variant in Spring Framework 6
 inline fun <reified T> JdbcOperations.queryForList(sql: String, args: Array<out Any>): List<T> =
-		queryForList(sql, T::class.java, args)
+		queryForList(sql, args, T::class.java)
+
 
 /**
  * Extension for [JdbcOperations.query] providing a ResultSetExtractor-like function

spring-jdbc/src/main/resources/org/springframework/jdbc/support/sql-error-codes.xml

@@ -247,7 +247,7 @@
 			<value>03000,42000,42601,42602,42622,42804,42P01</value>
 		</property>
 		<property name="duplicateKeyCodes">
-			<value>23505</value>
+			<value>21000,23505</value>
 		</property>
 		<property name="dataIntegrityViolationCodes">
 			<value>23000,23502,23503,23514</value>

spring-jdbc/src/test/java/org/springframework/jdbc/core/namedparam/NamedParameterJdbcTemplateTests.java

@@ -561,10 +561,11 @@ public class NamedParameterJdbcTemplateTests {
 
 	@Test
 	public void testBatchUpdateWithSqlParameterSourcePlusTypeInfo() throws Exception {
-		SqlParameterSource[] ids = new SqlParameterSource[2];
-		ids[0] = new MapSqlParameterSource().addValue("id", 100, Types.NUMERIC);
-		ids[1] = new MapSqlParameterSource().addValue("id", 200, Types.NUMERIC);
-		final int[] rowsAffected = new int[] {1, 2};
+		SqlParameterSource[] ids = new SqlParameterSource[3];
+		ids[0] = new MapSqlParameterSource().addValue("id", null, Types.NULL);
+		ids[1] = new MapSqlParameterSource().addValue("id", 100, Types.NUMERIC);
+		ids[2] = new MapSqlParameterSource().addValue("id", 200, Types.NUMERIC);
+		final int[] rowsAffected = new int[] {1, 2, 3};
 
 		given(preparedStatement.executeBatch()).willReturn(rowsAffected);
 		given(connection.getMetaData()).willReturn(databaseMetaData);
@@ -572,13 +573,15 @@ public class NamedParameterJdbcTemplateTests {
 
 		int[] actualRowsAffected = namedParameterTemplate.batchUpdate(
 				"UPDATE NOSUCHTABLE SET DATE_DISPATCHED = SYSDATE WHERE ID = :id", ids);
-		assertThat(actualRowsAffected.length == 2).as("executed 2 updates").isTrue();
+		assertThat(actualRowsAffected.length == 3).as("executed 3 updates").isTrue();
 		assertThat(actualRowsAffected[0]).isEqualTo(rowsAffected[0]);
 		assertThat(actualRowsAffected[1]).isEqualTo(rowsAffected[1]);
+		assertThat(actualRowsAffected[2]).isEqualTo(rowsAffected[2]);
 		verify(connection).prepareStatement("UPDATE NOSUCHTABLE SET DATE_DISPATCHED = SYSDATE WHERE ID = ?");
+		verify(preparedStatement).setNull(1, Types.NULL);
 		verify(preparedStatement).setObject(1, 100, Types.NUMERIC);
 		verify(preparedStatement).setObject(1, 200, Types.NUMERIC);
-		verify(preparedStatement, times(2)).addBatch();
+		verify(preparedStatement, times(3)).addBatch();
 		verify(preparedStatement, atLeastOnce()).close();
 		verify(connection, atLeastOnce()).close();
 	}

spring-jdbc/src/test/kotlin/org/springframework/jdbc/core/JdbcOperationsExtensionsTests.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors
+ * Copyright 2002-2021 the original author or authors
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -67,11 +67,12 @@ class JdbcOperationsExtensionsTests {
 	}
 
 	@Test
+	@Suppress("DEPRECATION")
 	fun `queryForObject with reified type parameters and args`() {
-		val args = arrayOf(3)
-		every { template.queryForObject(sql, any<Class<Int>>(), args) } returns 2
+		val args = arrayOf(3, 4)
+		every { template.queryForObject(sql, args, any<Class<Int>>()) } returns 2
 		assertThat(template.queryForObject<Int>(sql, args)).isEqualTo(2)
-		verify { template.queryForObject(sql, any<Class<Int>>(), args) }
+		verify { template.queryForObject(sql, args, any<Class<Int>>()) }
 	}
 
 	@Test
@@ -93,12 +94,13 @@ class JdbcOperationsExtensionsTests {
 	}
 
 	@Test
+	@Suppress("DEPRECATION")
 	fun `queryForList with reified type parameters and args`() {
 		val list = listOf(1, 2, 3)
-		val args = arrayOf(3)
-		every { template.queryForList(sql, any<Class<Int>>(), args) } returns list
+		val args = arrayOf(3, 4)
+		every { template.queryForList(sql, args, any<Class<Int>>()) } returns list
 		template.queryForList<Int>(sql, args)
-		verify { template.queryForList(sql, any<Class<Int>>(), args) }
+		verify { template.queryForList(sql, args, any<Class<Int>>()) }
 	}
 
 	@Test

spring-messaging/src/main/java/org/springframework/messaging/converter/KotlinSerializationJsonMessageConverter.java

@@ -94,6 +94,7 @@ public class KotlinSerializationJsonMessageConverter extends AbstractJsonMessage
 	 * Tries to find a serializer that can marshall or unmarshall instances of the given type
 	 * using kotlinx.serialization. If no serializer can be found, an exception is thrown.
 	 * <p>Resolved serializers are cached and cached results are returned on successive calls.
+	 * TODO Avoid relying on throwing exception when https://github.com/Kotlin/kotlinx.serialization/pull/1164 is fixed
 	 * @param type the type to find a serializer for
 	 * @return a resolved serializer for the given type
 	 * @throws RuntimeException if no serializer supporting the given type can be found

spring-messaging/src/main/java/org/springframework/messaging/handler/annotation/reactive/PayloadMethodArgumentResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -38,6 +38,7 @@ import org.springframework.core.annotation.AnnotationUtils;
 import org.springframework.core.codec.Decoder;
 import org.springframework.core.codec.DecodingException;
 import org.springframework.core.io.buffer.DataBuffer;
+import org.springframework.core.io.buffer.DataBufferUtils;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageHeaders;
@@ -232,6 +233,7 @@ public class PayloadMethodArgumentResolver implements HandlerMethodArgumentResol
 			if (decoder.canDecode(elementType, mimeType)) {
 				if (adapter != null && adapter.isMultiValue()) {
 					Flux<?> flux = content
+							.filter(this::nonEmptyDataBuffer)
 							.map(buffer -> decoder.decode(buffer, elementType, mimeType, hints))
 							.onErrorResume(ex -> Flux.error(handleReadError(parameter, message, ex)));
 					if (isContentRequired) {
@@ -245,6 +247,7 @@ public class PayloadMethodArgumentResolver implements HandlerMethodArgumentResol
 				else {
 					// Single-value (with or without reactive type wrapper)
 					Mono<?> mono = content.next()
+							.filter(this::nonEmptyDataBuffer)
 							.map(buffer -> decoder.decode(buffer, elementType, mimeType, hints))
 							.onErrorResume(ex -> Mono.error(handleReadError(parameter, message, ex)));
 					if (isContentRequired) {
@@ -262,6 +265,14 @@ public class PayloadMethodArgumentResolver implements HandlerMethodArgumentResol
 				message, parameter, "Cannot decode to [" + targetType + "]" + message));
 	}
 
+	private boolean nonEmptyDataBuffer(DataBuffer buffer) {
+		if (buffer.readableByteCount() > 0) {
+			return true;
+		}
+		DataBufferUtils.release(buffer);
+		return false;
+	}
+
 	private Throwable handleReadError(MethodParameter parameter, Message<?> message, Throwable ex) {
 		return ex instanceof DecodingException ?
 				new MethodArgumentResolutionException(message, parameter, "Failed to read HTTP message", ex) : ex;

spring-messaging/src/main/java/org/springframework/messaging/handler/invocation/AbstractExceptionHandlerMethodResolver.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -34,10 +34,24 @@ import org.springframework.util.ConcurrentReferenceHashMap;
  *
  * @author Rossen Stoyanchev
  * @author Juergen Hoeller
+ * @author Sam Brannen
  * @since 4.0
  */
 public abstract class AbstractExceptionHandlerMethodResolver {
 
+	private static final Method NO_MATCHING_EXCEPTION_HANDLER_METHOD;
+
+	static {
+		try {
+			NO_MATCHING_EXCEPTION_HANDLER_METHOD =
+					AbstractExceptionHandlerMethodResolver.class.getDeclaredMethod("noMatchingExceptionHandler");
+		}
+		catch (NoSuchMethodException ex) {
+			throw new IllegalStateException("Expected method not found: " + ex);
+		}
+	}
+
+
 	private final Map<Class<? extends Throwable>, Method> mappedMethods = new HashMap<>(16);
 
 	private final Map<Class<? extends Throwable>, Method> exceptionLookupCache = new ConcurrentReferenceHashMap<>(16);
@@ -52,9 +66,9 @@ public abstract class AbstractExceptionHandlerMethodResolver {
 	}
 
 	/**
-	 * Extract the exceptions this method handles.This implementation looks for
+	 * Extract the exceptions this method handles. This implementation looks for
 	 * sub-classes of Throwable in the method signature.
-	 * The method is static to ensure safe use from sub-class constructors.
+	 * <p>The method is static to ensure safe use from sub-class constructors.
 	 */
 	@SuppressWarnings("unchecked")
 	protected static List<Class<? extends Throwable>> getExceptionsFromMethodSignature(Method method) {
@@ -80,7 +94,7 @@ public abstract class AbstractExceptionHandlerMethodResolver {
 
 	/**
 	 * Find a {@link Method} to handle the given exception.
-	 * Use {@link ExceptionDepthComparator} if more than one match is found.
+	 * <p>Uses {@link ExceptionDepthComparator} if more than one match is found.
 	 * @param exception the exception
 	 * @return a Method to handle the exception, or {@code null} if none found
 	 */
@@ -99,6 +113,7 @@ public abstract class AbstractExceptionHandlerMethodResolver {
 	/**
 	 * Find a {@link Method} to handle the given exception type. This can be
 	 * useful if an {@link Exception} instance is not available (e.g. for tools).
+	 * <p>Uses {@link ExceptionDepthComparator} if more than one match is found.
 	 * @param exceptionType the exception type
 	 * @return a Method to handle the exception, or {@code null} if none found
 	 * @since 4.3.1
@@ -110,11 +125,12 @@ public abstract class AbstractExceptionHandlerMethodResolver {
 			method = getMappedMethod(exceptionType);
 			this.exceptionLookupCache.put(exceptionType, method);
 		}
-		return method;
+		return (method != NO_MATCHING_EXCEPTION_HANDLER_METHOD ? method : null);
 	}
 
 	/**
-	 * Return the {@link Method} mapped to the given exception type, or {@code null} if none.
+	 * Return the {@link Method} mapped to the given exception type, or
+	 * {@link #NO_MATCHING_EXCEPTION_HANDLER_METHOD} if none.
 	 */
 	@Nullable
 	private Method getMappedMethod(Class<? extends Throwable> exceptionType) {
@@ -125,12 +141,21 @@ public abstract class AbstractExceptionHandlerMethodResolver {
 			}
 		}
 		if (!matches.isEmpty()) {
-			matches.sort(new ExceptionDepthComparator(exceptionType));
+			if (matches.size() > 1) {
+				matches.sort(new ExceptionDepthComparator(exceptionType));
+			}
 			return this.mappedMethods.get(matches.get(0));
 		}
 		else {
-			return null;
+			return NO_MATCHING_EXCEPTION_HANDLER_METHOD;
 		}
 	}
 
+	/**
+	 * For the {@link #NO_MATCHING_EXCEPTION_HANDLER_METHOD} constant.
+	 */
+	@SuppressWarnings("unused")
+	private void noMatchingExceptionHandler() {
+	}
+
 }

spring-messaging/src/main/java/org/springframework/messaging/rsocket/DefaultMetadataExtractor.java

@@ -31,6 +31,8 @@ import io.rsocket.Payload;
 import io.rsocket.metadata.CompositeMetadata;
 import io.rsocket.metadata.RoutingMetadata;
 import io.rsocket.metadata.WellKnownMimeType;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 
 import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.core.ResolvableType;
@@ -52,6 +54,9 @@ import org.springframework.util.MimeType;
  */
 public class DefaultMetadataExtractor implements MetadataExtractor, MetadataExtractorRegistry {
 
+	private static final Log logger = LogFactory.getLog(DefaultMetadataExtractor.class);
+
+
 	private final List<Decoder<?>> decoders;
 
 	private final Map<String, EntryExtractor<?>> registrations = new HashMap<>();
@@ -119,6 +124,10 @@ public class DefaultMetadataExtractor implements MetadataExtractor, MetadataExtr
 		else {
 			extractEntry(payload.metadata().slice(), metadataMimeType.toString(), result);
 		}
+		if (logger.isDebugEnabled()) {
+			logger.debug("Values extracted from metadata: " + result +
+					" with registrations for " + this.registrations.keySet() + ".");
+		}
 		return result;
 	}
 
@@ -175,7 +184,7 @@ public class DefaultMetadataExtractor implements MetadataExtractor, MetadataExtr
 
 		@Override
 		public String toString() {
-			return "mimeType=" + this.mimeType + ", targetType=" + this.targetType;
+			return "\"" + this.mimeType + "\" => " + this.targetType;
 		}
 	}
 

spring-messaging/src/main/java/org/springframework/messaging/simp/config/AbstractMessageBrokerConfiguration.java

@@ -71,18 +71,18 @@ import org.springframework.validation.Validator;
  * Provides essential configuration for handling messages with simple messaging
  * protocols such as STOMP.
  *
- * <p>{@link #clientInboundChannel()} and {@link #clientOutboundChannel()} deliver
+ * <p>{@link #clientInboundChannel(TaskExecutor)} and {@link #clientOutboundChannel(TaskExecutor)} deliver
  * messages to and from remote clients to several message handlers such as the
  * following.
  * <ul>
- * <li>{@link #simpAnnotationMethodMessageHandler()}</li>
- * <li>{@link #simpleBrokerMessageHandler()}</li>
- * <li>{@link #stompBrokerRelayMessageHandler()}</li>
- * <li>{@link #userDestinationMessageHandler()}</li>
+ * <li>{@link #simpAnnotationMethodMessageHandler(AbstractSubscribableChannel, AbstractSubscribableChannel, SimpMessagingTemplate, CompositeMessageConverter)}</li>
+ * <li>{@link #simpleBrokerMessageHandler(AbstractSubscribableChannel, AbstractSubscribableChannel, AbstractSubscribableChannel, UserDestinationResolver)}</li>
+ * <li>{@link #stompBrokerRelayMessageHandler(AbstractSubscribableChannel, AbstractSubscribableChannel, AbstractSubscribableChannel, UserDestinationMessageHandler, MessageHandler, UserDestinationResolver)}</li>
+ * <li>{@link #userDestinationMessageHandler(AbstractSubscribableChannel, AbstractSubscribableChannel, AbstractSubscribableChannel, UserDestinationResolver)}</li>
  * </ul>
  *
- * <p>{@link #brokerChannel()} delivers messages from within the application to the
- * the respective message handlers. {@link #brokerMessagingTemplate()} can be injected
+ * <p>{@link #brokerChannel(AbstractSubscribableChannel, AbstractSubscribableChannel, TaskExecutor)} delivers messages from within the application to the
+ * the respective message handlers. {@link #brokerMessagingTemplate(AbstractSubscribableChannel, AbstractSubscribableChannel, AbstractSubscribableChannel, CompositeMessageConverter)} can be injected
  * into any application component to send messages.
  *
  * <p>Subclasses are responsible for the parts of the configuration that feed messages
@@ -90,6 +90,7 @@ import org.springframework.validation.Validator;
  *
  * @author Rossen Stoyanchev
  * @author Brian Clozel
+ * @author Sebastien Deleuze
  * @since 4.0
  */
 public abstract class AbstractMessageBrokerConfiguration implements ApplicationContextAware {
@@ -147,8 +148,8 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 
 
 	@Bean
-	public AbstractSubscribableChannel clientInboundChannel() {
-		ExecutorSubscribableChannel channel = new ExecutorSubscribableChannel(clientInboundChannelExecutor());
+	public AbstractSubscribableChannel clientInboundChannel(TaskExecutor clientInboundChannelExecutor) {
+		ExecutorSubscribableChannel channel = new ExecutorSubscribableChannel(clientInboundChannelExecutor);
 		channel.setLogger(SimpLogging.forLog(channel.getLogger()));
 		ChannelRegistration reg = getClientInboundChannelRegistration();
 		if (reg.hasInterceptors()) {
@@ -183,8 +184,8 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	@Bean
-	public AbstractSubscribableChannel clientOutboundChannel() {
-		ExecutorSubscribableChannel channel = new ExecutorSubscribableChannel(clientOutboundChannelExecutor());
+	public AbstractSubscribableChannel clientOutboundChannel(TaskExecutor clientOutboundChannelExecutor) {
+		ExecutorSubscribableChannel channel = new ExecutorSubscribableChannel(clientOutboundChannelExecutor);
 		channel.setLogger(SimpLogging.forLog(channel.getLogger()));
 		ChannelRegistration reg = getClientOutboundChannelRegistration();
 		if (reg.hasInterceptors()) {
@@ -219,10 +220,11 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	@Bean
-	public AbstractSubscribableChannel brokerChannel() {
-		ChannelRegistration reg = getBrokerRegistry().getBrokerChannelRegistration();
+	public AbstractSubscribableChannel brokerChannel(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel, TaskExecutor brokerChannelExecutor) {
+		ChannelRegistration reg = getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getBrokerChannelRegistration();
 		ExecutorSubscribableChannel channel = (reg.hasTaskExecutor() ?
-				new ExecutorSubscribableChannel(brokerChannelExecutor()) : new ExecutorSubscribableChannel());
+				new ExecutorSubscribableChannel(brokerChannelExecutor) : new ExecutorSubscribableChannel());
 		reg.interceptors(new ImmutableMessageChannelInterceptor());
 		channel.setLogger(SimpLogging.forLog(channel.getLogger()));
 		channel.setInterceptors(reg.getInterceptors());
@@ -230,8 +232,9 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	@Bean
-	public TaskExecutor brokerChannelExecutor() {
-		ChannelRegistration reg = getBrokerRegistry().getBrokerChannelRegistration();
+	public TaskExecutor brokerChannelExecutor(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel) {
+		ChannelRegistration reg = getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getBrokerChannelRegistration();
 		ThreadPoolTaskExecutor executor;
 		if (reg.hasTaskExecutor()) {
 			executor = reg.taskExecutor().getTaskExecutor();
@@ -251,9 +254,10 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	 * An accessor for the {@link MessageBrokerRegistry} that ensures its one-time creation
 	 * and initialization through {@link #configureMessageBroker(MessageBrokerRegistry)}.
 	 */
-	protected final MessageBrokerRegistry getBrokerRegistry() {
+	protected final MessageBrokerRegistry getBrokerRegistry(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel) {
 		if (this.brokerRegistry == null) {
-			MessageBrokerRegistry registry = new MessageBrokerRegistry(clientInboundChannel(), clientOutboundChannel());
+			MessageBrokerRegistry registry = new MessageBrokerRegistry(clientInboundChannel, clientOutboundChannel);
 			configureMessageBroker(registry);
 			this.brokerRegistry = registry;
 		}
@@ -272,15 +276,20 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	 * configuration classes.
 	 */
 	@Nullable
-	public final PathMatcher getPathMatcher() {
-		return getBrokerRegistry().getPathMatcher();
+	public final PathMatcher getPathMatcher(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel) {
+		return getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getPathMatcher();
 	}
 
 	@Bean
-	public SimpAnnotationMethodMessageHandler simpAnnotationMethodMessageHandler() {
-		SimpAnnotationMethodMessageHandler handler = createAnnotationMethodMessageHandler();
-		handler.setDestinationPrefixes(getBrokerRegistry().getApplicationDestinationPrefixes());
-		handler.setMessageConverter(brokerMessageConverter());
+	public SimpAnnotationMethodMessageHandler simpAnnotationMethodMessageHandler(
+			AbstractSubscribableChannel clientInboundChannel, AbstractSubscribableChannel clientOutboundChannel,
+			SimpMessagingTemplate brokerMessagingTemplate, CompositeMessageConverter brokerMessageConverter) {
+		SimpAnnotationMethodMessageHandler handler = createAnnotationMethodMessageHandler(clientInboundChannel,
+				clientOutboundChannel, brokerMessagingTemplate);
+		MessageBrokerRegistry brokerRegistry = getBrokerRegistry(clientInboundChannel, clientOutboundChannel);
+		handler.setDestinationPrefixes(brokerRegistry.getApplicationDestinationPrefixes());
+		handler.setMessageConverter(brokerMessageConverter);
 		handler.setValidator(simpValidator());
 
 		List<HandlerMethodArgumentResolver> argumentResolvers = new ArrayList<>();
@@ -291,7 +300,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 		addReturnValueHandlers(returnValueHandlers);
 		handler.setCustomReturnValueHandlers(returnValueHandlers);
 
-		PathMatcher pathMatcher = getBrokerRegistry().getPathMatcher();
+		PathMatcher pathMatcher = brokerRegistry.getPathMatcher();
 		if (pathMatcher != null) {
 			handler.setPathMatcher(pathMatcher);
 		}
@@ -302,11 +311,12 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	 * Protected method for plugging in a custom subclass of
 	 * {@link org.springframework.messaging.simp.annotation.support.SimpAnnotationMethodMessageHandler
 	 * SimpAnnotationMethodMessageHandler}.
-	 * @since 4.2
+	 * @since 5.3.2
 	 */
-	protected SimpAnnotationMethodMessageHandler createAnnotationMethodMessageHandler() {
-		return new SimpAnnotationMethodMessageHandler(clientInboundChannel(),
-				clientOutboundChannel(), brokerMessagingTemplate());
+	protected SimpAnnotationMethodMessageHandler createAnnotationMethodMessageHandler(
+			AbstractSubscribableChannel clientInboundChannel, AbstractSubscribableChannel clientOutboundChannel,
+			SimpMessagingTemplate brokerMessagingTemplate) {
+		return new SimpAnnotationMethodMessageHandler(clientInboundChannel, clientOutboundChannel, brokerMessagingTemplate);
 	}
 
 	protected void addArgumentResolvers(List<HandlerMethodArgumentResolver> argumentResolvers) {
@@ -317,48 +327,56 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 
 	@Bean
 	@Nullable
-	public AbstractBrokerMessageHandler simpleBrokerMessageHandler() {
-		SimpleBrokerMessageHandler handler = getBrokerRegistry().getSimpleBroker(brokerChannel());
+	public AbstractBrokerMessageHandler simpleBrokerMessageHandler(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel, AbstractSubscribableChannel brokerChannel,
+			UserDestinationResolver userDestinationResolver) {
+		SimpleBrokerMessageHandler handler = getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getSimpleBroker(brokerChannel);
 		if (handler == null) {
 			return null;
 		}
-		updateUserDestinationResolver(handler);
+		updateUserDestinationResolver(handler, userDestinationResolver);
 		return handler;
 	}
 
-	private void updateUserDestinationResolver(AbstractBrokerMessageHandler handler) {
+	private void updateUserDestinationResolver(AbstractBrokerMessageHandler handler, UserDestinationResolver userDestinationResolver) {
 		Collection<String> prefixes = handler.getDestinationPrefixes();
 		if (!prefixes.isEmpty() && !prefixes.iterator().next().startsWith("/")) {
-			((DefaultUserDestinationResolver) userDestinationResolver()).setRemoveLeadingSlash(true);
+			((DefaultUserDestinationResolver) userDestinationResolver).setRemoveLeadingSlash(true);
 		}
 	}
 
 	@Bean
 	@Nullable
-	public AbstractBrokerMessageHandler stompBrokerRelayMessageHandler() {
-		StompBrokerRelayMessageHandler handler = getBrokerRegistry().getStompBrokerRelay(brokerChannel());
+	public AbstractBrokerMessageHandler stompBrokerRelayMessageHandler(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel, AbstractSubscribableChannel brokerChannel,
+			UserDestinationMessageHandler userDestinationMessageHandler, @Nullable MessageHandler userRegistryMessageHandler,
+			UserDestinationResolver userDestinationResolver) {
+		MessageBrokerRegistry brokerRegistry = getBrokerRegistry(clientInboundChannel, clientOutboundChannel);
+		StompBrokerRelayMessageHandler handler = brokerRegistry.getStompBrokerRelay(brokerChannel);
 		if (handler == null) {
 			return null;
 		}
 		Map<String, MessageHandler> subscriptions = new HashMap<>(4);
-		String destination = getBrokerRegistry().getUserDestinationBroadcast();
+		String destination = brokerRegistry.getUserDestinationBroadcast();
 		if (destination != null) {
-			subscriptions.put(destination, userDestinationMessageHandler());
+			subscriptions.put(destination, userDestinationMessageHandler);
 		}
-		destination = getBrokerRegistry().getUserRegistryBroadcast();
+		destination = brokerRegistry.getUserRegistryBroadcast();
 		if (destination != null) {
-			subscriptions.put(destination, userRegistryMessageHandler());
+			subscriptions.put(destination, userRegistryMessageHandler);
 		}
 		handler.setSystemSubscriptions(subscriptions);
-		updateUserDestinationResolver(handler);
+		updateUserDestinationResolver(handler, userDestinationResolver);
 		return handler;
 	}
 
 	@Bean
-	public UserDestinationMessageHandler userDestinationMessageHandler() {
-		UserDestinationMessageHandler handler = new UserDestinationMessageHandler(clientInboundChannel(),
-				brokerChannel(), userDestinationResolver());
-		String destination = getBrokerRegistry().getUserDestinationBroadcast();
+	public UserDestinationMessageHandler userDestinationMessageHandler(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel, AbstractSubscribableChannel brokerChannel,
+			UserDestinationResolver userDestinationResolver) {
+		UserDestinationMessageHandler handler = new UserDestinationMessageHandler(clientInboundChannel,
+				brokerChannel, userDestinationResolver);
+		String destination = getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getUserDestinationBroadcast();
 		if (destination != null) {
 			handler.setBroadcastDestination(destination);
 		}
@@ -367,15 +385,17 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 
 	@Bean
 	@Nullable
-	public MessageHandler userRegistryMessageHandler() {
-		if (getBrokerRegistry().getUserRegistryBroadcast() == null) {
+	public MessageHandler userRegistryMessageHandler(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel, SimpUserRegistry userRegistry,
+			SimpMessagingTemplate brokerMessagingTemplate, TaskScheduler messageBrokerTaskScheduler) {
+		MessageBrokerRegistry brokerRegistry = getBrokerRegistry(clientInboundChannel, clientOutboundChannel);
+		if (brokerRegistry.getUserRegistryBroadcast() == null) {
 			return null;
 		}
-		SimpUserRegistry userRegistry = userRegistry();
 		Assert.isInstanceOf(MultiServerUserRegistry.class, userRegistry, "MultiServerUserRegistry required");
 		return new UserRegistryMessageHandler((MultiServerUserRegistry) userRegistry,
-				brokerMessagingTemplate(), getBrokerRegistry().getUserRegistryBroadcast(),
-				messageBrokerTaskScheduler());
+				brokerMessagingTemplate, brokerRegistry.getUserRegistryBroadcast(),
+				messageBrokerTaskScheduler);
 	}
 
 	// Expose alias for 4.1 compatibility
@@ -389,13 +409,15 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	@Bean
-	public SimpMessagingTemplate brokerMessagingTemplate() {
-		SimpMessagingTemplate template = new SimpMessagingTemplate(brokerChannel());
-		String prefix = getBrokerRegistry().getUserDestinationPrefix();
+	public SimpMessagingTemplate brokerMessagingTemplate(AbstractSubscribableChannel brokerChannel,
+			AbstractSubscribableChannel clientInboundChannel, AbstractSubscribableChannel clientOutboundChannel,
+			CompositeMessageConverter brokerMessageConverter) {
+		SimpMessagingTemplate template = new SimpMessagingTemplate(brokerChannel);
+		String prefix = getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getUserDestinationPrefix();
 		if (prefix != null) {
 			template.setUserDestinationPrefix(prefix);
 		}
-		template.setMessageConverter(brokerMessageConverter());
+		template.setMessageConverter(brokerMessageConverter);
 		return template;
 	}
 
@@ -441,9 +463,10 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	@Bean
-	public UserDestinationResolver userDestinationResolver() {
-		DefaultUserDestinationResolver resolver = new DefaultUserDestinationResolver(userRegistry());
-		String prefix = getBrokerRegistry().getUserDestinationPrefix();
+	public UserDestinationResolver userDestinationResolver(SimpUserRegistry userRegistry,
+			AbstractSubscribableChannel clientInboundChannel, AbstractSubscribableChannel clientOutboundChannel) {
+		DefaultUserDestinationResolver resolver = new DefaultUserDestinationResolver(userRegistry);
+		String prefix = getBrokerRegistry(clientInboundChannel, clientOutboundChannel).getUserDestinationPrefix();
 		if (prefix != null) {
 			resolver.setUserDestinationPrefix(prefix);
 		}
@@ -452,12 +475,14 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 
 	@Bean
 	@SuppressWarnings("deprecation")
-	public SimpUserRegistry userRegistry() {
+	public SimpUserRegistry userRegistry(AbstractSubscribableChannel clientInboundChannel,
+			AbstractSubscribableChannel clientOutboundChannel) {
 		SimpUserRegistry registry = createLocalUserRegistry();
+		MessageBrokerRegistry brokerRegistry = getBrokerRegistry(clientInboundChannel, clientOutboundChannel);
 		if (registry == null) {
-			registry = createLocalUserRegistry(getBrokerRegistry().getUserRegistryOrder());
+			registry = createLocalUserRegistry(brokerRegistry.getUserRegistryOrder());
 		}
-		boolean broadcast = getBrokerRegistry().getUserRegistryBroadcast() != null;
+		boolean broadcast = brokerRegistry.getUserRegistryBroadcast() != null;
 		return (broadcast ? new MultiServerUserRegistry(registry) : registry);
 	}
 

spring-messaging/src/main/java/org/springframework/messaging/support/MessageHeaderAccessor.java

@@ -378,13 +378,14 @@ public class MessageHeaderAccessor {
 	 * {@link #copyHeadersIfAbsent(Map)} to avoid overwriting values.
 	 */
 	public void copyHeaders(@Nullable Map<String, ?> headersToCopy) {
-		if (headersToCopy != null) {
-			headersToCopy.forEach((key, value) -> {
-				if (!isReadOnly(key)) {
-					setHeader(key, value);
-				}
-			});
+		if (headersToCopy == null || this.headers == headersToCopy) {
+			return;
 		}
+		headersToCopy.forEach((key, value) -> {
+			if (!isReadOnly(key)) {
+				setHeader(key, value);
+			}
+		});
 	}
 
 	/**
@@ -392,13 +393,14 @@ public class MessageHeaderAccessor {
 	 * <p>This operation will <em>not</em> overwrite any existing values.
 	 */
 	public void copyHeadersIfAbsent(@Nullable Map<String, ?> headersToCopy) {
-		if (headersToCopy != null) {
-			headersToCopy.forEach((key, value) -> {
-				if (!isReadOnly(key)) {
-					setHeaderIfAbsent(key, value);
-				}
-			});
+		if (headersToCopy == null || this.headers == headersToCopy) {
+			return;
 		}
+		headersToCopy.forEach((key, value) -> {
+			if (!isReadOnly(key)) {
+				setHeaderIfAbsent(key, value);
+			}
+		});
 	}
 
 	protected boolean isReadOnly(String headerName) {

spring-messaging/src/main/java/org/springframework/messaging/support/NativeMessageHeaderAccessor.java

@@ -75,6 +75,8 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 			@SuppressWarnings("unchecked")
 			Map<String, List<String>> map = (Map<String, List<String>>) getHeader(NATIVE_HEADERS);
 			if (map != null) {
+				// setHeader checks for equality but we need copy of native headers
+				setHeader(NATIVE_HEADERS, null);
 				setHeader(NATIVE_HEADERS, new LinkedMultiValueMap<>(map));
 			}
 		}
@@ -103,6 +105,8 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 		if (isMutable()) {
 			Map<String, List<String>> map = getNativeHeaders();
 			if (map != null) {
+				// setHeader checks for equality but we need immutable wrapper
+				setHeader(NATIVE_HEADERS, null);
 				setHeader(NATIVE_HEADERS, Collections.unmodifiableMap(map));
 			}
 			super.setImmutable();
@@ -110,31 +114,34 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 	}
 
 	@Override
-	public void setHeader(String name, @Nullable Object value) {
-		if (name.equalsIgnoreCase(NATIVE_HEADERS)) {
-			// Force removal since setHeader checks for equality
-			super.setHeader(NATIVE_HEADERS, null);
+	public void copyHeaders(@Nullable Map<String, ?> headersToCopy) {
+		if (headersToCopy == null) {
+			return;
 		}
-		super.setHeader(name, value);
+
+		@SuppressWarnings("unchecked")
+		Map<String, List<String>> map = (Map<String, List<String>>) headersToCopy.get(NATIVE_HEADERS);
+		if (map != null && map != getNativeHeaders()) {
+			map.forEach(this::setNativeHeaderValues);
+		}
+
+		// setHeader checks for equality, native headers should be equal by now
+		super.copyHeaders(headersToCopy);
 	}
 
 	@Override
-	@SuppressWarnings("unchecked")
-	public void copyHeaders(@Nullable Map<String, ?> headersToCopy) {
-		if (headersToCopy != null) {
-			Map<String, List<String>> nativeHeaders = getNativeHeaders();
-			Map<String, List<String>> map = (Map<String, List<String>>) headersToCopy.get(NATIVE_HEADERS);
-			if (map != null) {
-				if (nativeHeaders != null) {
-					nativeHeaders.putAll(map);
-				}
-				else {
-					nativeHeaders = new LinkedMultiValueMap<>(map);
-				}
-			}
-			super.copyHeaders(headersToCopy);
-			setHeader(NATIVE_HEADERS, nativeHeaders);
+	public void copyHeadersIfAbsent(@Nullable Map<String, ?> headersToCopy) {
+		if (headersToCopy == null) {
+			return;
 		}
+
+		@SuppressWarnings("unchecked")
+		Map<String, List<String>> map = (Map<String, List<String>>) headersToCopy.get(NATIVE_HEADERS);
+		if (map != null && getNativeHeaders() == null) {
+			map.forEach(this::setNativeHeaderValues);
+		}
+
+		super.copyHeadersIfAbsent(headersToCopy);
 	}
 
 	/**
@@ -201,6 +208,30 @@ public class NativeMessageHeaderAccessor extends MessageHeaderAccessor {
 		}
 	}
 
+	/**
+	 * Variant of {@link #addNativeHeader(String, String)} for all values.
+	 * @since 5.2.12
+	 */
+	public void setNativeHeaderValues(String name, @Nullable List<String> values) {
+		Assert.state(isMutable(), "Already immutable");
+		Map<String, List<String>> map = getNativeHeaders();
+		if (values == null) {
+			if (map != null && map.get(name) != null) {
+				setModified(true);
+				map.remove(name);
+			}
+			return;
+		}
+		if (map == null) {
+			map = new LinkedMultiValueMap<>(3);
+			setHeader(NATIVE_HEADERS, map);
+		}
+		if (!ObjectUtils.nullSafeEquals(values, getHeader(name))) {
+			setModified(true);
+			map.put(name, new ArrayList<>(values));
+		}
+	}
+
 	/**
 	 * Add the specified native header value to existing values.
 	 * <p>In order for this to work, the accessor must be {@link #isMutable()

spring-messaging/src/test/java/org/springframework/messaging/rsocket/RSocketClientToServerIntegrationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2021 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,7 +19,6 @@ package org.springframework.messaging.rsocket;
 import java.time.Duration;
 import java.util.concurrent.atomic.AtomicInteger;
 
-import io.rsocket.Payload;
 import io.rsocket.RSocket;
 import io.rsocket.SocketAcceptor;
 import io.rsocket.core.RSocketServer;
@@ -43,6 +42,7 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.messaging.handler.annotation.Header;
 import org.springframework.messaging.handler.annotation.MessageExceptionHandler;
 import org.springframework.messaging.handler.annotation.MessageMapping;
+import org.springframework.messaging.handler.annotation.Payload;
 import org.springframework.messaging.rsocket.annotation.ConnectMapping;
 import org.springframework.messaging.rsocket.annotation.support.RSocketMessageHandler;
 import org.springframework.stereotype.Controller;
@@ -164,6 +164,12 @@ public class RSocketClientToServerIntegrationTests {
 				.verify(Duration.ofSeconds(5));
 	}
 
+	@Test // gh-26344
+	public void echoChannelWithEmptyInput() {
+		Flux<String> result = requester.route("echo-channel-empty").data(Flux.empty()).retrieveFlux(String.class);
+		StepVerifier.create(result).verifyComplete();
+	}
+
 	@Test
 	public void metadataPush() {
 		Flux.just("bar", "baz")
@@ -254,6 +260,11 @@ public class RSocketClientToServerIntegrationTests {
 			return payloads.delayElements(Duration.ofMillis(10)).map(payload -> payload + " async");
 		}
 
+		@MessageMapping("echo-channel-empty")
+		Flux<String> echoChannelEmpty(@Payload(required = false) Flux<String> payloads) {
+			return payloads.map(payload -> payload + " echoed");
+		}
+
 		@MessageMapping("thrown-exception")
 		Mono<String> handleAndThrow(String payload) {
 			throw new IllegalArgumentException("Invalid input error");
@@ -338,29 +349,29 @@ public class RSocketClientToServerIntegrationTests {
 		}
 
 		@Override
-		public Mono<Void> fireAndForget(Payload payload) {
+		public Mono<Void> fireAndForget(io.rsocket.Payload payload) {
 			return this.delegate.fireAndForget(payload)
 					.doOnSuccess(aVoid -> this.fireAndForgetCount.incrementAndGet());
 		}
 
 		@Override
-		public Mono<Void> metadataPush(Payload payload) {
+		public Mono<Void> metadataPush(io.rsocket.Payload payload) {
 			return this.delegate.metadataPush(payload)
 					.doOnSuccess(aVoid -> this.metadataPushCount.incrementAndGet());
 		}
 
 		@Override
-		public Mono<Payload> requestResponse(Payload payload) {
+		public Mono<io.rsocket.Payload> requestResponse(io.rsocket.Payload payload) {
 			return this.delegate.requestResponse(payload);
 		}
 
 		@Override
-		public Flux<Payload> requestStream(Payload payload) {
+		public Flux<io.rsocket.Payload> requestStream(io.rsocket.Payload payload) {
 			return this.delegate.requestStream(payload);
 		}
 
 		@Override
-		public Flux<Payload> requestChannel(Publisher<Payload> payloads) {
+		public Flux<io.rsocket.Payload> requestChannel(Publisher<io.rsocket.Payload> payloads) {
 			return this.delegate.requestChannel(payloads);
 		}
 	}

spring-messaging/src/test/java/org/springframework/messaging/simp/config/MessageBrokerConfigurationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2019 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,6 +30,7 @@ import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.context.support.StaticApplicationContext;
 import org.springframework.core.Ordered;
+import org.springframework.core.task.TaskExecutor;
 import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
@@ -594,19 +595,20 @@ public class MessageBrokerConfigurationTests {
 
 		@Override
 		@Bean
-		public AbstractSubscribableChannel clientInboundChannel() {
+		public AbstractSubscribableChannel clientInboundChannel(TaskExecutor clientInboundChannelExecutor) {
 			return new TestChannel();
 		}
 
 		@Override
 		@Bean
-		public AbstractSubscribableChannel clientOutboundChannel() {
+		public AbstractSubscribableChannel clientOutboundChannel(TaskExecutor clientOutboundChannelExecutor) {
 			return new TestChannel();
 		}
 
 		@Override
 		@Bean
-		public AbstractSubscribableChannel brokerChannel() {
+		public AbstractSubscribableChannel brokerChannel(AbstractSubscribableChannel clientInboundChannel,
+				AbstractSubscribableChannel clientOutboundChannel, TaskExecutor brokerChannelExecutor) {
 			return new TestChannel();
 		}
 	}
@@ -680,20 +682,21 @@ public class MessageBrokerConfigurationTests {
 
 		@Override
 		@Bean
-		public AbstractSubscribableChannel clientInboundChannel() {
+		public AbstractSubscribableChannel clientInboundChannel(TaskExecutor clientInboundChannelExecutor) {
 			// synchronous
 			return new ExecutorSubscribableChannel(null);
 		}
 
 		@Override
 		@Bean
-		public AbstractSubscribableChannel clientOutboundChannel() {
+		public AbstractSubscribableChannel clientOutboundChannel(TaskExecutor clientOutboundChannelExecutor) {
 			return new TestChannel();
 		}
 
 		@Override
 		@Bean
-		public AbstractSubscribableChannel brokerChannel() {
+		public AbstractSubscribableChannel brokerChannel(AbstractSubscribableChannel clientInboundChannel,
+				AbstractSubscribableChannel clientOutboundChannel, TaskExecutor brokerChannelExecutor) {
 			// synchronous
 			return new ExecutorSubscribableChannel(null);
 		}

spring-messaging/src/test/java/org/springframework/messaging/support/NativeMessageHeaderAccessorTests.java

@@ -226,19 +226,46 @@ public class NativeMessageHeaderAccessorTests {
 
 	@Test // gh-25821
 	void copyImmutableToMutable() {
-		NativeMessageHeaderAccessor source = new NativeMessageHeaderAccessor();
-		source.addNativeHeader("foo", "bar");
-		Message<String> message = MessageBuilder.createMessage("payload", source.getMessageHeaders());
+		NativeMessageHeaderAccessor sourceAccessor = new NativeMessageHeaderAccessor();
+		sourceAccessor.addNativeHeader("foo", "bar");
+		Message<String> source = MessageBuilder.createMessage("payload", sourceAccessor.getMessageHeaders());
 
-		NativeMessageHeaderAccessor target = new NativeMessageHeaderAccessor();
-		target.copyHeaders(message.getHeaders());
-		target.setLeaveMutable(true);
-		message = MessageBuilder.createMessage(message.getPayload(), target.getMessageHeaders());
+		NativeMessageHeaderAccessor targetAccessor = new NativeMessageHeaderAccessor();
+		targetAccessor.copyHeaders(source.getHeaders());
+		targetAccessor.setLeaveMutable(true);
+		Message<?> target = MessageBuilder.createMessage(source.getPayload(), targetAccessor.getMessageHeaders());
 
-		MessageHeaderAccessor accessor = MessageHeaderAccessor.getMutableAccessor(message);
+		MessageHeaderAccessor accessor = MessageHeaderAccessor.getMutableAccessor(target);
 		assertThat(accessor.isMutable());
 		((NativeMessageHeaderAccessor) accessor).addNativeHeader("foo", "baz");
 		assertThat(((NativeMessageHeaderAccessor) accessor).getNativeHeader("foo")).containsExactly("bar", "baz");
 	}
 
+	@Test // gh-25821
+	void copyIfAbsentImmutableToMutable() {
+		NativeMessageHeaderAccessor sourceAccessor = new NativeMessageHeaderAccessor();
+		sourceAccessor.addNativeHeader("foo", "bar");
+		Message<String> source = MessageBuilder.createMessage("payload", sourceAccessor.getMessageHeaders());
+
+		MessageHeaderAccessor targetAccessor = new NativeMessageHeaderAccessor();
+		targetAccessor.copyHeadersIfAbsent(source.getHeaders());
+		targetAccessor.setLeaveMutable(true);
+		Message<?> target = MessageBuilder.createMessage(source.getPayload(), targetAccessor.getMessageHeaders());
+
+		MessageHeaderAccessor accessor = MessageHeaderAccessor.getMutableAccessor(target);
+		assertThat(accessor.isMutable());
+		((NativeMessageHeaderAccessor) accessor).addNativeHeader("foo", "baz");
+		assertThat(((NativeMessageHeaderAccessor) accessor).getNativeHeader("foo")).containsExactly("bar", "baz");
+	}
+
+	@Test // gh-26155
+	void copySelf() {
+		NativeMessageHeaderAccessor accessor = new NativeMessageHeaderAccessor();
+		accessor.addNativeHeader("foo", "bar");
+		accessor.setHeader("otherHeader", "otherHeaderValue");
+		accessor.setLeaveMutable(true);
+
+		// Does not fail with ConcurrentModificationException
+		accessor.copyHeaders(accessor.getMessageHeaders());
+	}
 }

spring-orm/src/main/java/org/springframework/orm/jpa/AbstractEntityManagerFactoryBean.java

@@ -418,10 +418,13 @@ public abstract class AbstractEntityManagerFactoryBean implements
 					String message = ex.getMessage();
 					String causeString = cause.toString();
 					if (!message.endsWith(causeString)) {
-						throw new PersistenceException(message + "; nested exception is " + causeString, cause);
+						ex = new PersistenceException(message + "; nested exception is " + causeString, cause);
 					}
 				}
 			}
+			if (logger.isErrorEnabled()) {
+				logger.error("Failed to initialize JPA EntityManagerFactory: " + ex.getMessage());
+			}
 			throw ex;
 		}
 

spring-orm/src/main/java/org/springframework/orm/jpa/vendor/HibernateJpaVendorAdapter.java

@@ -48,9 +48,9 @@ import org.springframework.lang.Nullable;
  * EntityManager. Developed and tested against Hibernate 5.3 and 5.4;
  * backwards-compatible with Hibernate 5.2 at runtime on a best-effort basis.
  *
- * <p>Exposes Hibernate's persistence provider and EntityManager extension interface,
- * and adapts {@link AbstractJpaVendorAdapter}'s common configuration settings.
- * Also supports the detection of annotated packages (through
+ * <p>Exposes Hibernate's persistence provider and Hibernate's Session as extended
+ * EntityManager interface, and adapts {@link AbstractJpaVendorAdapter}'s common
+ * configuration settings. Also supports the detection of annotated packages (through
  * {@link org.springframework.orm.jpa.persistenceunit.SmartPersistenceUnitInfo#getManagedPackages()}),
  * e.g. containing Hibernate {@link org.hibernate.annotations.FilterDef} annotations,
  * along with Spring-driven entity scanning which requires no {@code persistence.xml}
@@ -82,8 +82,8 @@ public class HibernateJpaVendorAdapter extends AbstractJpaVendorAdapter {
 
 	public HibernateJpaVendorAdapter() {
 		this.persistenceProvider = new SpringHibernateJpaPersistenceProvider();
-		this.entityManagerFactoryInterface = SessionFactory.class;
-		this.entityManagerInterface = Session.class;
+		this.entityManagerFactoryInterface = SessionFactory.class;  // as of Spring 5.3
+		this.entityManagerInterface = Session.class;  // as of Spring 5.3
 	}
 
 

spring-test/src/main/java/org/springframework/mock/web/MockMultipartFile.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2020 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -21,6 +21,7 @@ import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
 
+import org.springframework.lang.NonNull;
 import org.springframework.lang.Nullable;
 import org.springframework.util.Assert;
 import org.springframework.util.FileCopyUtils;
@@ -42,10 +43,10 @@ public class MockMultipartFile implements MultipartFile {
 
 	private final String name;
 
-	private String originalFilename;
+	private final String originalFilename;
 
 	@Nullable
-	private String contentType;
+	private final String contentType;
 
 	private final byte[] content;
 
@@ -79,7 +80,7 @@ public class MockMultipartFile implements MultipartFile {
 	public MockMultipartFile(
 			String name, @Nullable String originalFilename, @Nullable String contentType, @Nullable byte[] content) {
 
-		Assert.hasLength(name, "Name must not be null");
+		Assert.hasLength(name, "Name must not be empty");
 		this.name = name;
 		this.originalFilename = (originalFilename != null ? originalFilename : "");
 		this.contentType = contentType;
@@ -108,6 +109,7 @@ public class MockMultipartFile implements MultipartFile {
 	}
 
 	@Override
+	@NonNull
 	public String getOriginalFilename() {
 		return this.originalFilename;
 	}