diff --git a/spring-aop/src/main/java/org/aopalliance/intercept/MethodInterceptor.java b/spring-aop/src/main/java/org/aopalliance/intercept/MethodInterceptor.java
index c08fd7443f2..8239b0e63b7 100644
--- a/spring-aop/src/main/java/org/aopalliance/intercept/MethodInterceptor.java
+++ b/spring-aop/src/main/java/org/aopalliance/intercept/MethodInterceptor.java
@@ -39,6 +39,7 @@ package org.aopalliance.intercept;
  *
  * @author Rod Johnson
  */
+@FunctionalInterface
 public interface MethodInterceptor extends Interceptor {
 	
 	/**
diff --git a/spring-aop/src/main/java/org/springframework/aop/ClassFilter.java b/spring-aop/src/main/java/org/springframework/aop/ClassFilter.java
index 9cb86c02c0b..822515f7592 100644
--- a/spring-aop/src/main/java/org/springframework/aop/ClassFilter.java
+++ b/spring-aop/src/main/java/org/springframework/aop/ClassFilter.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -27,6 +27,7 @@ package org.springframework.aop;
  * @see Pointcut
  * @see MethodMatcher
  */
+@FunctionalInterface
 public interface ClassFilter {
 
 	/**
diff --git a/spring-aop/src/main/java/org/springframework/aop/framework/autoproxy/TargetSourceCreator.java b/spring-aop/src/main/java/org/springframework/aop/framework/autoproxy/TargetSourceCreator.java
index 67f9638ce45..a962c3518b9 100644
--- a/spring-aop/src/main/java/org/springframework/aop/framework/autoproxy/TargetSourceCreator.java
+++ b/spring-aop/src/main/java/org/springframework/aop/framework/autoproxy/TargetSourceCreator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -29,6 +29,7 @@ import org.springframework.aop.TargetSource;
  * @author Rod Johnson
  * @author Juergen Hoeller
  */
+@FunctionalInterface
 public interface TargetSourceCreator {
 
 	/**
diff --git a/spring-aop/src/main/java/org/springframework/aop/interceptor/AsyncUncaughtExceptionHandler.java b/spring-aop/src/main/java/org/springframework/aop/interceptor/AsyncUncaughtExceptionHandler.java
index 933e3024c5f..2914e53ef5d 100644
--- a/spring-aop/src/main/java/org/springframework/aop/interceptor/AsyncUncaughtExceptionHandler.java
+++ b/spring-aop/src/main/java/org/springframework/aop/interceptor/AsyncUncaughtExceptionHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -29,6 +29,7 @@ import java.lang.reflect.Method;
  * @author Stephane Nicoll
  * @since 4.1
  */
+@FunctionalInterface
 public interface AsyncUncaughtExceptionHandler {
 
 	/**
diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/config/BeanFactoryPostProcessor.java b/spring-beans/src/main/java/org/springframework/beans/factory/config/BeanFactoryPostProcessor.java
index 8cfbb7645ff..e0d5b07e757 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/config/BeanFactoryPostProcessor.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/config/BeanFactoryPostProcessor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -42,6 +42,7 @@ import org.springframework.beans.BeansException;
  * @see BeanPostProcessor
  * @see PropertyResourceConfigurer
  */
+@FunctionalInterface
 public interface BeanFactoryPostProcessor {
 
 	/**
diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/parsing/SourceExtractor.java b/spring-beans/src/main/java/org/springframework/beans/factory/parsing/SourceExtractor.java
index 0b0fe96658c..ed9248fdf28 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/parsing/SourceExtractor.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/parsing/SourceExtractor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -33,6 +33,7 @@ import org.springframework.core.io.Resource;
  * @see org.springframework.beans.BeanMetadataElement#getSource()
  * @see org.springframework.beans.factory.config.BeanDefinition
  */
+@FunctionalInterface
 public interface SourceExtractor {
 
 	/**
diff --git a/spring-beans/src/main/java/org/springframework/beans/factory/xml/NamespaceHandlerResolver.java b/spring-beans/src/main/java/org/springframework/beans/factory/xml/NamespaceHandlerResolver.java
index d8ccc410506..7874ed2f195 100644
--- a/spring-beans/src/main/java/org/springframework/beans/factory/xml/NamespaceHandlerResolver.java
+++ b/spring-beans/src/main/java/org/springframework/beans/factory/xml/NamespaceHandlerResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -25,6 +25,7 @@ package org.springframework.beans.factory.xml;
  * @see NamespaceHandler
  * @see org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader
  */
+@FunctionalInterface
 public interface NamespaceHandlerResolver {
 
 	/**
diff --git a/spring-context-support/src/main/java/org/springframework/mail/javamail/MimeMessagePreparator.java b/spring-context-support/src/main/java/org/springframework/mail/javamail/MimeMessagePreparator.java
index 2740bc19c71..4aa82246af3 100644
--- a/spring-context-support/src/main/java/org/springframework/mail/javamail/MimeMessagePreparator.java
+++ b/spring-context-support/src/main/java/org/springframework/mail/javamail/MimeMessagePreparator.java
@@ -36,6 +36,7 @@ import javax.mail.internet.MimeMessage;
  * @see JavaMailSender#send(MimeMessagePreparator[])
  * @see MimeMessageHelper
  */
+@FunctionalInterface
 public interface MimeMessagePreparator {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/cache/Cache.java b/spring-context/src/main/java/org/springframework/cache/Cache.java
index ebd26020471..3124461b2e5 100644
--- a/spring-context/src/main/java/org/springframework/cache/Cache.java
+++ b/spring-context/src/main/java/org/springframework/cache/Cache.java
@@ -145,6 +145,7 @@ public interface Cache {
 	/**
 	 * A (wrapper) object representing a cache value.
 	 */
+	@FunctionalInterface
 	interface ValueWrapper {
 
 		/**
diff --git a/spring-context/src/main/java/org/springframework/cache/annotation/AnnotationCacheOperationSource.java b/spring-context/src/main/java/org/springframework/cache/annotation/AnnotationCacheOperationSource.java
index 858bbbbc274..f685cc2b674 100644
--- a/spring-context/src/main/java/org/springframework/cache/annotation/AnnotationCacheOperationSource.java
+++ b/spring-context/src/main/java/org/springframework/cache/annotation/AnnotationCacheOperationSource.java
@@ -181,6 +181,7 @@ public class AnnotationCacheOperationSource extends AbstractFallbackCacheOperati
 	 * Callback interface providing {@link CacheOperation} instance(s) based on
 	 * a given {@link CacheAnnotationParser}.
 	 */
+	@FunctionalInterface
 	protected interface CacheOperationProvider {
 
 		/**
diff --git a/spring-context/src/main/java/org/springframework/cache/interceptor/CacheOperationInvoker.java b/spring-context/src/main/java/org/springframework/cache/interceptor/CacheOperationInvoker.java
index 8901ba1945c..aa5d50452be 100644
--- a/spring-context/src/main/java/org/springframework/cache/interceptor/CacheOperationInvoker.java
+++ b/spring-context/src/main/java/org/springframework/cache/interceptor/CacheOperationInvoker.java
@@ -27,6 +27,7 @@ package org.springframework.cache.interceptor;
  * @author Stephane Nicoll
  * @since 4.1
  */
+@FunctionalInterface
 public interface CacheOperationInvoker {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/cache/interceptor/CacheResolver.java b/spring-context/src/main/java/org/springframework/cache/interceptor/CacheResolver.java
index 4bf2fd02e6b..8b5b4be8339 100644
--- a/spring-context/src/main/java/org/springframework/cache/interceptor/CacheResolver.java
+++ b/spring-context/src/main/java/org/springframework/cache/interceptor/CacheResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,6 +28,7 @@ import org.springframework.cache.Cache;
  * @author Stephane Nicoll
  * @since 4.1
  */
+@FunctionalInterface
 public interface CacheResolver {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/cache/interceptor/KeyGenerator.java b/spring-context/src/main/java/org/springframework/cache/interceptor/KeyGenerator.java
index ad34f5b20af..0dbf048bf51 100644
--- a/spring-context/src/main/java/org/springframework/cache/interceptor/KeyGenerator.java
+++ b/spring-context/src/main/java/org/springframework/cache/interceptor/KeyGenerator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -27,6 +27,7 @@ import java.lang.reflect.Method;
  * @author Phillip Webb
  * @since 3.1
  */
+@FunctionalInterface
 public interface KeyGenerator {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/context/ApplicationListener.java b/spring-context/src/main/java/org/springframework/context/ApplicationListener.java
index 54d22825ff8..8cb0262f079 100644
--- a/spring-context/src/main/java/org/springframework/context/ApplicationListener.java
+++ b/spring-context/src/main/java/org/springframework/context/ApplicationListener.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -33,6 +33,7 @@ import java.util.EventListener;
  * @param <E> the specific ApplicationEvent subclass to listen to
  * @see org.springframework.context.event.ApplicationEventMulticaster
  */
+@FunctionalInterface
 public interface ApplicationListener<E extends ApplicationEvent> extends EventListener {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/context/annotation/Condition.java b/spring-context/src/main/java/org/springframework/context/annotation/Condition.java
index edc6c05b70a..2cdcc36cb82 100644
--- a/spring-context/src/main/java/org/springframework/context/annotation/Condition.java
+++ b/spring-context/src/main/java/org/springframework/context/annotation/Condition.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.type.AnnotatedTypeMetadata;
  * @see Conditional
  * @see ConditionContext
  */
+@FunctionalInterface
 public interface Condition {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassEnhancer.java b/spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassEnhancer.java
index 52c27a3ce0a..f239b2158ea 100644
--- a/spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassEnhancer.java
+++ b/spring-context/src/main/java/org/springframework/context/annotation/ConfigurationClassEnhancer.java
@@ -151,6 +151,7 @@ class ConfigurationClassEnhancer {
 	 * must remain public in order to allow access to subclasses generated from other
 	 * packages (i.e. user code).
 	 */
+	@FunctionalInterface
 	public interface EnhancedConfiguration extends BeanFactoryAware {
 	}
 
@@ -159,6 +160,7 @@ class ConfigurationClassEnhancer {
 	 * Conditional {@link Callback}.
 	 * @see ConditionalCallbackFilter
 	 */
+	@FunctionalInterface
 	private interface ConditionalCallback extends Callback {
 
 		boolean isMatch(Method candidateMethod);
diff --git a/spring-context/src/main/java/org/springframework/context/annotation/ScopeMetadataResolver.java b/spring-context/src/main/java/org/springframework/context/annotation/ScopeMetadataResolver.java
index 04fda90705a..0020b96e847 100644
--- a/spring-context/src/main/java/org/springframework/context/annotation/ScopeMetadataResolver.java
+++ b/spring-context/src/main/java/org/springframework/context/annotation/ScopeMetadataResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -25,6 +25,7 @@ import org.springframework.beans.factory.config.BeanDefinition;
  * @since 2.5
  * @see org.springframework.context.annotation.Scope
  */
+@FunctionalInterface
 public interface ScopeMetadataResolver {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/format/Parser.java b/spring-context/src/main/java/org/springframework/format/Parser.java
index ed62cc4e10d..f856ad95160 100644
--- a/spring-context/src/main/java/org/springframework/format/Parser.java
+++ b/spring-context/src/main/java/org/springframework/format/Parser.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -26,6 +26,7 @@ import java.util.Locale;
  * @since 3.0
  * @param <T> the type of object this Parser produces
  */
+@FunctionalInterface
 public interface Parser<T> {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/format/Printer.java b/spring-context/src/main/java/org/springframework/format/Printer.java
index ce2d5d85a8e..582735e113c 100644
--- a/spring-context/src/main/java/org/springframework/format/Printer.java
+++ b/spring-context/src/main/java/org/springframework/format/Printer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -25,6 +25,7 @@ import java.util.Locale;
  * @since 3.0
  * @param <T> the type of object this Printer prints
  */
+@FunctionalInterface
 public interface Printer<T> {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/jmx/export/MBeanExporter.java b/spring-context/src/main/java/org/springframework/jmx/export/MBeanExporter.java
index c50ceb6228a..c58632be435 100644
--- a/spring-context/src/main/java/org/springframework/jmx/export/MBeanExporter.java
+++ b/spring-context/src/main/java/org/springframework/jmx/export/MBeanExporter.java
@@ -1077,7 +1077,8 @@ public class MBeanExporter extends MBeanRegistrationSupport implements MBeanExpo
 	/**
 	 * Internal callback interface for the autodetection process.
 	 */
-	private static interface AutodetectCallback {
+	@FunctionalInterface
+	private interface AutodetectCallback {
 
 		/**
 		 * Called during the autodetection process to decide whether
diff --git a/spring-context/src/main/java/org/springframework/jmx/export/naming/ObjectNamingStrategy.java b/spring-context/src/main/java/org/springframework/jmx/export/naming/ObjectNamingStrategy.java
index cfbda068c0d..8ff3511946e 100644
--- a/spring-context/src/main/java/org/springframework/jmx/export/naming/ObjectNamingStrategy.java
+++ b/spring-context/src/main/java/org/springframework/jmx/export/naming/ObjectNamingStrategy.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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 javax.management.ObjectName;
  * @see org.springframework.jmx.export.MBeanExporter
  * @see javax.management.ObjectName
  */
+@FunctionalInterface
 public interface ObjectNamingStrategy {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/jmx/export/notification/NotificationPublisher.java b/spring-context/src/main/java/org/springframework/jmx/export/notification/NotificationPublisher.java
index 068b7a5a603..85e6feae916 100644
--- a/spring-context/src/main/java/org/springframework/jmx/export/notification/NotificationPublisher.java
+++ b/spring-context/src/main/java/org/springframework/jmx/export/notification/NotificationPublisher.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -42,6 +42,7 @@ import javax.management.Notification;
  * @see NotificationPublisherAware
  * @see org.springframework.jmx.export.MBeanExporter
  */
+@FunctionalInterface
 public interface NotificationPublisher {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/jndi/JndiCallback.java b/spring-context/src/main/java/org/springframework/jndi/JndiCallback.java
index c7845ec84cc..c6c76826f7e 100644
--- a/spring-context/src/main/java/org/springframework/jndi/JndiCallback.java
+++ b/spring-context/src/main/java/org/springframework/jndi/JndiCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -33,6 +33,7 @@ import javax.naming.NamingException;
  * @see JndiTemplate
  * @see org.springframework.jdbc.core.JdbcTemplate
  */
+@FunctionalInterface
 public interface JndiCallback<T> {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/scheduling/annotation/SchedulingConfigurer.java b/spring-context/src/main/java/org/springframework/scheduling/annotation/SchedulingConfigurer.java
index 095ff700a7c..f782a970edd 100644
--- a/spring-context/src/main/java/org/springframework/scheduling/annotation/SchedulingConfigurer.java
+++ b/spring-context/src/main/java/org/springframework/scheduling/annotation/SchedulingConfigurer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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 org.springframework.scheduling.config.ScheduledTaskRegistrar;
  * @see EnableScheduling
  * @see ScheduledTaskRegistrar
  */
+@FunctionalInterface
 public interface SchedulingConfigurer {
 
 	/**
diff --git a/spring-context/src/main/java/org/springframework/scripting/groovy/GroovyObjectCustomizer.java b/spring-context/src/main/java/org/springframework/scripting/groovy/GroovyObjectCustomizer.java
index cb4f5b1c17d..7d1adabe804 100644
--- a/spring-context/src/main/java/org/springframework/scripting/groovy/GroovyObjectCustomizer.java
+++ b/spring-context/src/main/java/org/springframework/scripting/groovy/GroovyObjectCustomizer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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 groovy.lang.GroovyObject;
  * @since 2.0.2
  * @see GroovyScriptFactory
  */
+@FunctionalInterface
 public interface GroovyObjectCustomizer {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/MethodIntrospector.java b/spring-core/src/main/java/org/springframework/core/MethodIntrospector.java
index dbd594c4637..0f8e3965564 100644
--- a/spring-core/src/main/java/org/springframework/core/MethodIntrospector.java
+++ b/spring-core/src/main/java/org/springframework/core/MethodIntrospector.java
@@ -146,6 +146,7 @@ public abstract class MethodIntrospector {
 	 * A callback interface for metadata lookup on a given method.
 	 * @param <T> the type of metadata returned
 	 */
+	@FunctionalInterface
 	public interface MetadataLookup<T> {
 
 		/**
diff --git a/spring-core/src/main/java/org/springframework/core/OrderComparator.java b/spring-core/src/main/java/org/springframework/core/OrderComparator.java
index 3d976d94af1..39e27ac56cb 100644
--- a/spring-core/src/main/java/org/springframework/core/OrderComparator.java
+++ b/spring-core/src/main/java/org/springframework/core/OrderComparator.java
@@ -203,6 +203,7 @@ public class OrderComparator implements Comparator<Object> {
 	 * Strategy interface to provide an order source for a given object.
 	 * @since 4.1
 	 */
+	@FunctionalInterface
 	public interface OrderSourceProvider {
 
 		/**
diff --git a/spring-core/src/main/java/org/springframework/core/convert/converter/Converter.java b/spring-core/src/main/java/org/springframework/core/convert/converter/Converter.java
index 0223b5d4002..0d3c5dc14fa 100644
--- a/spring-core/src/main/java/org/springframework/core/convert/converter/Converter.java
+++ b/spring-core/src/main/java/org/springframework/core/convert/converter/Converter.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,6 +28,7 @@ package org.springframework.core.convert.converter;
  * @param <S> the source type
  * @param <T> the target type
  */
+@FunctionalInterface
 public interface Converter<S, T> {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/io/ProtocolResolver.java b/spring-core/src/main/java/org/springframework/core/io/ProtocolResolver.java
index 700c866e7fa..6d808c37c36 100644
--- a/spring-core/src/main/java/org/springframework/core/io/ProtocolResolver.java
+++ b/spring-core/src/main/java/org/springframework/core/io/ProtocolResolver.java
@@ -27,6 +27,7 @@ package org.springframework.core.io;
  * @since 4.3
  * @see DefaultResourceLoader#addProtocolResolver
  */
+@FunctionalInterface
 public interface ProtocolResolver {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/serializer/Deserializer.java b/spring-core/src/main/java/org/springframework/core/serializer/Deserializer.java
index f64fbdf762f..5cc8a9d195c 100644
--- a/spring-core/src/main/java/org/springframework/core/serializer/Deserializer.java
+++ b/spring-core/src/main/java/org/springframework/core/serializer/Deserializer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -26,6 +26,7 @@ import java.io.InputStream;
  * @author Mark Fisher
  * @since 3.0.5
  */
+@FunctionalInterface
 public interface Deserializer<T> {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/serializer/Serializer.java b/spring-core/src/main/java/org/springframework/core/serializer/Serializer.java
index 8af65195243..70f329cdc81 100644
--- a/spring-core/src/main/java/org/springframework/core/serializer/Serializer.java
+++ b/spring-core/src/main/java/org/springframework/core/serializer/Serializer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -26,6 +26,7 @@ import java.io.OutputStream;
  * @author Mark Fisher
  * @since 3.0.5
  */
+@FunctionalInterface
 public interface Serializer<T> {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/task/TaskDecorator.java b/spring-core/src/main/java/org/springframework/core/task/TaskDecorator.java
index d36a3ab3919..d61b584f524 100644
--- a/spring-core/src/main/java/org/springframework/core/task/TaskDecorator.java
+++ b/spring-core/src/main/java/org/springframework/core/task/TaskDecorator.java
@@ -32,6 +32,7 @@ package org.springframework.core.task;
  * @see TaskExecutor#execute(Runnable)
  * @see SimpleAsyncTaskExecutor#setTaskDecorator
  */
+@FunctionalInterface
 public interface TaskDecorator {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/task/TaskExecutor.java b/spring-core/src/main/java/org/springframework/core/task/TaskExecutor.java
index bf8b9f910e8..573cb02abf5 100644
--- a/spring-core/src/main/java/org/springframework/core/task/TaskExecutor.java
+++ b/spring-core/src/main/java/org/springframework/core/task/TaskExecutor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -35,6 +35,7 @@ import java.util.concurrent.Executor;
  * @since 2.0
  * @see java.util.concurrent.Executor
  */
+@FunctionalInterface
 public interface TaskExecutor extends Executor {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/core/type/filter/TypeFilter.java b/spring-core/src/main/java/org/springframework/core/type/filter/TypeFilter.java
index bdcf33524d5..5bd4d1b22d0 100644
--- a/spring-core/src/main/java/org/springframework/core/type/filter/TypeFilter.java
+++ b/spring-core/src/main/java/org/springframework/core/type/filter/TypeFilter.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * Copyright 2002-2016 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.core.type.classreading.MetadataReaderFactory;
  * @author Mark Fisher
  * @since 2.5
  */
+@FunctionalInterface
 public interface TypeFilter {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/util/AutoPopulatingList.java b/spring-core/src/main/java/org/springframework/util/AutoPopulatingList.java
index 1f42d01defc..0d10f6a1f81 100644
--- a/spring-core/src/main/java/org/springframework/util/AutoPopulatingList.java
+++ b/spring-core/src/main/java/org/springframework/util/AutoPopulatingList.java
@@ -243,6 +243,7 @@ public class AutoPopulatingList<E> implements List<E>, Serializable {
 	 * Factory interface for creating elements for an index-based access
 	 * data structure such as a {@link java.util.List}.
 	 */
+	@FunctionalInterface
 	public interface ElementFactory<E> {
 
 		/**
diff --git a/spring-core/src/main/java/org/springframework/util/ErrorHandler.java b/spring-core/src/main/java/org/springframework/util/ErrorHandler.java
index a43ee8b6590..506777ef0ff 100644
--- a/spring-core/src/main/java/org/springframework/util/ErrorHandler.java
+++ b/spring-core/src/main/java/org/springframework/util/ErrorHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -25,6 +25,7 @@ package org.springframework.util;
  * @author Mark Fisher
  * @since 3.0
  */
+@FunctionalInterface
 public interface ErrorHandler {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java b/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java
index 206b147c78d..094173916e6 100644
--- a/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java
+++ b/spring-core/src/main/java/org/springframework/util/PropertyPlaceholderHelper.java
@@ -212,7 +212,8 @@ public class PropertyPlaceholderHelper {
 	/**
 	 * Strategy interface used to resolve replacement values for placeholders contained in Strings.
 	 */
-	public static interface PlaceholderResolver {
+	@FunctionalInterface
+	public interface PlaceholderResolver {
 
 		/**
 		 * Resolve the supplied placeholder name to the replacement value.
diff --git a/spring-core/src/main/java/org/springframework/util/ReflectionUtils.java b/spring-core/src/main/java/org/springframework/util/ReflectionUtils.java
index fd2df57be1b..558db143214 100644
--- a/spring-core/src/main/java/org/springframework/util/ReflectionUtils.java
+++ b/spring-core/src/main/java/org/springframework/util/ReflectionUtils.java
@@ -755,6 +755,7 @@ public abstract class ReflectionUtils {
 	/**
 	 * Action to take on each method.
 	 */
+	@FunctionalInterface
 	public interface MethodCallback {
 
 		/**
@@ -768,6 +769,7 @@ public abstract class ReflectionUtils {
 	/**
 	 * Callback optionally used to filter methods to be operated on by a method callback.
 	 */
+	@FunctionalInterface
 	public interface MethodFilter {
 
 		/**
@@ -781,6 +783,7 @@ public abstract class ReflectionUtils {
 	/**
 	 * Callback interface invoked on each field in the hierarchy.
 	 */
+	@FunctionalInterface
 	public interface FieldCallback {
 
 		/**
@@ -794,6 +797,7 @@ public abstract class ReflectionUtils {
 	/**
 	 * Callback optionally used to filter fields to be operated on by a field callback.
 	 */
+	@FunctionalInterface
 	public interface FieldFilter {
 
 		/**
diff --git a/spring-core/src/main/java/org/springframework/util/StringValueResolver.java b/spring-core/src/main/java/org/springframework/util/StringValueResolver.java
index acc77c1e645..fe7799d3fc0 100644
--- a/spring-core/src/main/java/org/springframework/util/StringValueResolver.java
+++ b/spring-core/src/main/java/org/springframework/util/StringValueResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2007 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -26,6 +26,7 @@ package org.springframework.util;
  * @see org.springframework.beans.factory.config.BeanDefinitionVisitor#BeanDefinitionVisitor(StringValueResolver)
  * @see org.springframework.beans.factory.config.PropertyPlaceholderConfigurer
  */
+@FunctionalInterface
 public interface StringValueResolver {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/util/backoff/BackOff.java b/spring-core/src/main/java/org/springframework/util/backoff/BackOff.java
index 0543ac917ac..f3bc0ac6158 100644
--- a/spring-core/src/main/java/org/springframework/util/backoff/BackOff.java
+++ b/spring-core/src/main/java/org/springframework/util/backoff/BackOff.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -43,6 +43,7 @@ package org.springframework.util.backoff;
  * @since 4.1
  * @see BackOffExecution
  */
+@FunctionalInterface
 public interface BackOff {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/util/backoff/BackOffExecution.java b/spring-core/src/main/java/org/springframework/util/backoff/BackOffExecution.java
index 4204285ceb5..117bbd7f9fa 100644
--- a/spring-core/src/main/java/org/springframework/util/backoff/BackOffExecution.java
+++ b/spring-core/src/main/java/org/springframework/util/backoff/BackOffExecution.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -25,6 +25,7 @@ package org.springframework.util.backoff;
  * @since 4.1
  * @see BackOff
  */
+@FunctionalInterface
 public interface BackOffExecution {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/util/concurrent/FailureCallback.java b/spring-core/src/main/java/org/springframework/util/concurrent/FailureCallback.java
index 20f2142024c..f3304d0f8b5 100644
--- a/spring-core/src/main/java/org/springframework/util/concurrent/FailureCallback.java
+++ b/spring-core/src/main/java/org/springframework/util/concurrent/FailureCallback.java
@@ -22,6 +22,7 @@ package org.springframework.util.concurrent;
  * @author Sebastien Deleuze
  * @since 4.1
  */
+@FunctionalInterface
 public interface FailureCallback {
 
 	/**
diff --git a/spring-core/src/main/java/org/springframework/util/concurrent/SuccessCallback.java b/spring-core/src/main/java/org/springframework/util/concurrent/SuccessCallback.java
index b20bcad137d..bd1930c9e4c 100644
--- a/spring-core/src/main/java/org/springframework/util/concurrent/SuccessCallback.java
+++ b/spring-core/src/main/java/org/springframework/util/concurrent/SuccessCallback.java
@@ -22,6 +22,7 @@ package org.springframework.util.concurrent;
  * @author Sebastien Deleuze
  * @since 4.1
  */
+@FunctionalInterface
 public interface SuccessCallback<T> {
 
 	/**
diff --git a/spring-expression/src/main/java/org/springframework/expression/ConstructorResolver.java b/spring-expression/src/main/java/org/springframework/expression/ConstructorResolver.java
index 0019e8c3b15..30255ac2e61 100644
--- a/spring-expression/src/main/java/org/springframework/expression/ConstructorResolver.java
+++ b/spring-expression/src/main/java/org/springframework/expression/ConstructorResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,6 +28,7 @@ import org.springframework.core.convert.TypeDescriptor;
  * @author Andy Clement
  * @since 3.0
  */
+@FunctionalInterface
 public interface ConstructorResolver {
 
 	/**
diff --git a/spring-expression/src/main/java/org/springframework/expression/MethodFilter.java b/spring-expression/src/main/java/org/springframework/expression/MethodFilter.java
index d7c6e20cbdb..3cd2afef41e 100644
--- a/spring-expression/src/main/java/org/springframework/expression/MethodFilter.java
+++ b/spring-expression/src/main/java/org/springframework/expression/MethodFilter.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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 java.util.List;
  * @author Andy Clement
  * @since 3.0.1
  */
+@FunctionalInterface
 public interface MethodFilter {
 
 	/**
diff --git a/spring-expression/src/main/java/org/springframework/expression/TypeLocator.java b/spring-expression/src/main/java/org/springframework/expression/TypeLocator.java
index e9696268953..87018b4eaa1 100644
--- a/spring-expression/src/main/java/org/springframework/expression/TypeLocator.java
+++ b/spring-expression/src/main/java/org/springframework/expression/TypeLocator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -27,6 +27,7 @@ package org.springframework.expression;
  * @author Andy Clement
  * @since 3.0
  */
+@FunctionalInterface
 public interface TypeLocator {
 
 	/**
diff --git a/spring-expression/src/main/java/org/springframework/expression/spel/CodeFlow.java b/spring-expression/src/main/java/org/springframework/expression/spel/CodeFlow.java
index c503ea94a41..bdb9e2e60d0 100644
--- a/spring-expression/src/main/java/org/springframework/expression/spel/CodeFlow.java
+++ b/spring-expression/src/main/java/org/springframework/expression/spel/CodeFlow.java
@@ -838,12 +838,14 @@ public class CodeFlow implements Opcodes {
 		return clazzName;
 	}
 
+	@FunctionalInterface
 	public interface FieldAdder {
-		public void generateField(ClassWriter cw, CodeFlow codeflow);
+		void generateField(ClassWriter cw, CodeFlow codeflow);
 	}
 
+	@FunctionalInterface
 	public interface ClinitAdder {
-		public void generateCode(MethodVisitor mv, CodeFlow codeflow);
+		void generateCode(MethodVisitor mv, CodeFlow codeflow);
 	}
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCallback.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCallback.java
index 8ce3abbf353..434e243737b 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCallback.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -40,6 +40,7 @@ import org.springframework.dao.DataAccessException;
  * @see JdbcTemplate#execute(String, CallableStatementCallback)
  * @see JdbcTemplate#execute(CallableStatementCreator, CallableStatementCallback)
  */
+@FunctionalInterface
 public interface CallableStatementCallback<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCreator.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCreator.java
index b4175b86028..920640214ee 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCreator.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/CallableStatementCreator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -40,6 +40,7 @@ import java.sql.SQLException;
  * @see JdbcTemplate#call
  * @see SqlProvider
  */
+@FunctionalInterface
 public interface CallableStatementCreator {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ConnectionCallback.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ConnectionCallback.java
index 55a63039c3a..7c99bdc01a8 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ConnectionCallback.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ConnectionCallback.java
@@ -37,6 +37,7 @@ import org.springframework.dao.DataAccessException;
  * @see JdbcTemplate#query
  * @see JdbcTemplate#update
  */
+@FunctionalInterface
 public interface ConnectionCallback<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterMapper.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterMapper.java
index e333c738750..8198084ee22 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterMapper.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterMapper.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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 java.util.Map;
  * @see CallableStatementCreatorFactory#newCallableStatementCreator(ParameterMapper)
  * @see org.springframework.jdbc.object.StoredProcedure#execute(ParameterMapper)
  */
+@FunctionalInterface
 public interface ParameterMapper {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterizedPreparedStatementSetter.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterizedPreparedStatementSetter.java
index 500e1523e41..b69439d6f4b 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterizedPreparedStatementSetter.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ParameterizedPreparedStatementSetter.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -37,6 +37,7 @@ import java.sql.SQLException;
  * @since 3.1
  * @see JdbcTemplate#batchUpdate(String, java.util.Collection, int, ParameterizedPreparedStatementSetter)
  */
+@FunctionalInterface
 public interface ParameterizedPreparedStatementSetter<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCallback.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCallback.java
index 9c2cd0e9be0..3db375c7b95 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCallback.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCallback.java
@@ -40,6 +40,7 @@ import org.springframework.dao.DataAccessException;
  * @see JdbcTemplate#execute(String, PreparedStatementCallback)
  * @see JdbcTemplate#execute(PreparedStatementCreator, PreparedStatementCallback)
  */
+@FunctionalInterface
 public interface PreparedStatementCallback<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCreator.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCreator.java
index ee123ceed93..c6f39075fb6 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCreator.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementCreator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -40,6 +40,7 @@ import java.sql.SQLException;
  * @see JdbcTemplate#update(PreparedStatementCreator)
  * @see SqlProvider
  */
+@FunctionalInterface
 public interface PreparedStatementCreator {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementSetter.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementSetter.java
index 462eba3fafa..8978a7f532d 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementSetter.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/PreparedStatementSetter.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -40,6 +40,7 @@ import java.sql.SQLException;
  * @see JdbcTemplate#update(String, PreparedStatementSetter)
  * @see JdbcTemplate#query(String, PreparedStatementSetter, ResultSetExtractor)
  */
+@FunctionalInterface
 public interface PreparedStatementSetter {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ResultSetExtractor.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ResultSetExtractor.java
index 183b8b2b1bc..7ada08f7899 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/ResultSetExtractor.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/ResultSetExtractor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -46,6 +46,7 @@ import org.springframework.dao.DataAccessException;
  * @see RowMapper
  * @see org.springframework.jdbc.core.support.AbstractLobStreamingResultSetExtractor
  */
+@FunctionalInterface
 public interface ResultSetExtractor<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowCallbackHandler.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowCallbackHandler.java
index 47f1e4f57a4..3f592052d21 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowCallbackHandler.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowCallbackHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -42,6 +42,7 @@ import java.sql.SQLException;
  * @see ResultSetExtractor
  * @see RowCountCallbackHandler
  */
+@FunctionalInterface
 public interface RowCallbackHandler {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowMapper.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowMapper.java
index 48ac7c8d3eb..8e044a92903 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowMapper.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/RowMapper.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -45,6 +45,7 @@ import java.sql.SQLException;
  * @see ResultSetExtractor
  * @see org.springframework.jdbc.object.MappingSqlQuery
  */
+@FunctionalInterface
 public interface RowMapper<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/core/StatementCallback.java b/spring-jdbc/src/main/java/org/springframework/jdbc/core/StatementCallback.java
index 3edd3c2b67c..7fdb7101924 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/core/StatementCallback.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/core/StatementCallback.java
@@ -33,6 +33,7 @@ import org.springframework.dao.DataAccessException;
  * @since 16.03.2004
  * @see JdbcTemplate#execute(StatementCallback)
  */
+@FunctionalInterface
 public interface StatementCallback<T> {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/DatabasePopulator.java b/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/DatabasePopulator.java
index d72ee0cab3b..fc03cb6b8b7 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/DatabasePopulator.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/init/DatabasePopulator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -29,6 +29,7 @@ import java.sql.SQLException;
  * @see DatabasePopulatorUtils
  * @see DataSourceInitializer
  */
+@FunctionalInterface
 public interface DatabasePopulator {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/lookup/DataSourceLookup.java b/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/lookup/DataSourceLookup.java
index f4eff425d3e..1ab29a43377 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/lookup/DataSourceLookup.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/datasource/lookup/DataSourceLookup.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -29,6 +29,7 @@ import javax.sql.DataSource;
  * @since 2.0
  * @see org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager#setDataSourceLookup
  */
+@FunctionalInterface
 public interface DataSourceLookup {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/support/DatabaseMetaDataCallback.java b/spring-jdbc/src/main/java/org/springframework/jdbc/support/DatabaseMetaDataCallback.java
index abb9d7e33b3..8b283c2633e 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/support/DatabaseMetaDataCallback.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/support/DatabaseMetaDataCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,6 +28,7 @@ import java.sql.SQLException;
  * @author Thomas Risberg
  * @see JdbcUtils#extractDatabaseMetaData
  */
+@FunctionalInterface
 public interface DatabaseMetaDataCallback {
 
 	/**
diff --git a/spring-jdbc/src/main/java/org/springframework/jdbc/support/SQLExceptionTranslator.java b/spring-jdbc/src/main/java/org/springframework/jdbc/support/SQLExceptionTranslator.java
index 87a84c8dc15..193b1e1b1f4 100644
--- a/spring-jdbc/src/main/java/org/springframework/jdbc/support/SQLExceptionTranslator.java
+++ b/spring-jdbc/src/main/java/org/springframework/jdbc/support/SQLExceptionTranslator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -33,6 +33,7 @@ import org.springframework.dao.DataAccessException;
  * @author Juergen Hoeller
  * @see org.springframework.dao.DataAccessException
  */
+@FunctionalInterface
 public interface SQLExceptionTranslator {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/annotation/JmsListenerConfigurer.java b/spring-jms/src/main/java/org/springframework/jms/annotation/JmsListenerConfigurer.java
index 403e5bd3f07..5427a3d1e8a 100644
--- a/spring-jms/src/main/java/org/springframework/jms/annotation/JmsListenerConfigurer.java
+++ b/spring-jms/src/main/java/org/springframework/jms/annotation/JmsListenerConfigurer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -33,6 +33,7 @@ import org.springframework.jms.config.JmsListenerEndpointRegistrar;
  * @see EnableJms
  * @see JmsListenerEndpointRegistrar
  */
+@FunctionalInterface
 public interface JmsListenerConfigurer {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/core/BrowserCallback.java b/spring-jms/src/main/java/org/springframework/jms/core/BrowserCallback.java
index 563503eb075..c9f2b57790a 100644
--- a/spring-jms/src/main/java/org/springframework/jms/core/BrowserCallback.java
+++ b/spring-jms/src/main/java/org/springframework/jms/core/BrowserCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -31,6 +31,7 @@ import javax.jms.Session;
  * @see JmsTemplate#browse(BrowserCallback)
  * @see JmsTemplate#browseSelected(String, BrowserCallback)
  */
+@FunctionalInterface
 public interface BrowserCallback<T> {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/core/MessageCreator.java b/spring-jms/src/main/java/org/springframework/jms/core/MessageCreator.java
index 3f3d5c14ba9..213242d91d0 100644
--- a/spring-jms/src/main/java/org/springframework/jms/core/MessageCreator.java
+++ b/spring-jms/src/main/java/org/springframework/jms/core/MessageCreator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -35,6 +35,7 @@ import javax.jms.Session;
  * @author Mark Pollack
  * @since 1.1
  */
+@FunctionalInterface
 public interface MessageCreator {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/core/ProducerCallback.java b/spring-jms/src/main/java/org/springframework/jms/core/ProducerCallback.java
index 6297b67983e..af787263c71 100644
--- a/spring-jms/src/main/java/org/springframework/jms/core/ProducerCallback.java
+++ b/spring-jms/src/main/java/org/springframework/jms/core/ProducerCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -35,6 +35,7 @@ import javax.jms.Session;
  * @see JmsTemplate#execute(javax.jms.Destination, ProducerCallback)
  * @see JmsTemplate#execute(String, ProducerCallback)
  */
+@FunctionalInterface
 public interface ProducerCallback<T> {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/core/SessionCallback.java b/spring-jms/src/main/java/org/springframework/jms/core/SessionCallback.java
index 77c57614e2b..e81728e5af8 100644
--- a/spring-jms/src/main/java/org/springframework/jms/core/SessionCallback.java
+++ b/spring-jms/src/main/java/org/springframework/jms/core/SessionCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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 javax.jms.Session;
  * @since 1.1
  * @see JmsTemplate#execute(SessionCallback)
  */
+@FunctionalInterface
 public interface SessionCallback<T> {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/listener/SessionAwareMessageListener.java b/spring-jms/src/main/java/org/springframework/jms/listener/SessionAwareMessageListener.java
index 15a39df9226..c0946db2591 100644
--- a/spring-jms/src/main/java/org/springframework/jms/listener/SessionAwareMessageListener.java
+++ b/spring-jms/src/main/java/org/springframework/jms/listener/SessionAwareMessageListener.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -41,6 +41,7 @@ import javax.jms.Session;
  * @see org.springframework.jms.listener.endpoint.JmsMessageEndpointManager
  * @see javax.jms.MessageListener
  */
+@FunctionalInterface
 public interface SessionAwareMessageListener<M extends Message> {
 
 	/**
diff --git a/spring-jms/src/main/java/org/springframework/jms/support/destination/DestinationResolver.java b/spring-jms/src/main/java/org/springframework/jms/support/destination/DestinationResolver.java
index cd32ceae941..4a0d2cde4ed 100644
--- a/spring-jms/src/main/java/org/springframework/jms/support/destination/DestinationResolver.java
+++ b/spring-jms/src/main/java/org/springframework/jms/support/destination/DestinationResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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 javax.jms.Session;
  * @see org.springframework.jms.support.destination.DynamicDestinationResolver
  * @see org.springframework.jms.support.destination.JndiDestinationResolver
  */
+@FunctionalInterface
 public interface DestinationResolver {
 
 	/**
diff --git a/spring-messaging/src/main/java/org/springframework/messaging/MessageHandler.java b/spring-messaging/src/main/java/org/springframework/messaging/MessageHandler.java
index d5ed9adbd36..ac2a3ebbb4f 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/MessageHandler.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/MessageHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -23,6 +23,7 @@ package org.springframework.messaging;
  * @author Iwein Fuld
  * @since 4.0
  */
+@FunctionalInterface
 public interface MessageHandler {
 
 	/**
diff --git a/spring-messaging/src/main/java/org/springframework/messaging/converter/ContentTypeResolver.java b/spring-messaging/src/main/java/org/springframework/messaging/converter/ContentTypeResolver.java
index f9fe42fe6e8..afd7b7002c3 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/converter/ContentTypeResolver.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/converter/ContentTypeResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -25,6 +25,7 @@ import org.springframework.util.MimeType;
  * @author Rossen Stoyanchev
  * @since 4.0
  */
+@FunctionalInterface
 public interface ContentTypeResolver {
 
 	/**
diff --git a/spring-messaging/src/main/java/org/springframework/messaging/core/DestinationResolver.java b/spring-messaging/src/main/java/org/springframework/messaging/core/DestinationResolver.java
index 2521c05f6cc..bd50b234cf3 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/core/DestinationResolver.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/core/DestinationResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -23,6 +23,7 @@ package org.springframework.messaging.core;
  * @author Mark Fisher
  * @since 4.0
  */
+@FunctionalInterface
 public interface DestinationResolver<D> {
 
 	/**
diff --git a/spring-messaging/src/main/java/org/springframework/messaging/simp/user/SimpSubscriptionMatcher.java b/spring-messaging/src/main/java/org/springframework/messaging/simp/user/SimpSubscriptionMatcher.java
index 97261db047a..8f1fc3d8480 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/simp/user/SimpSubscriptionMatcher.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/simp/user/SimpSubscriptionMatcher.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -22,6 +22,7 @@ package org.springframework.messaging.simp.user;
  * @author Rossen Stoyanchev
  * @since 4.2
  */
+@FunctionalInterface
 public interface SimpSubscriptionMatcher {
 
 	/**
diff --git a/spring-messaging/src/main/java/org/springframework/messaging/simp/user/UserDestinationResolver.java b/spring-messaging/src/main/java/org/springframework/messaging/simp/user/UserDestinationResolver.java
index 2354c05f314..722067611a5 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/simp/user/UserDestinationResolver.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/simp/user/UserDestinationResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -34,6 +34,7 @@ import org.springframework.messaging.Message;
  * @see org.springframework.messaging.simp.user.DefaultUserDestinationResolver
  * @see UserDestinationMessageHandler
  */
+@FunctionalInterface
 public interface UserDestinationResolver {
 
 	/**
diff --git a/spring-messaging/src/main/java/org/springframework/messaging/tcp/ReconnectStrategy.java b/spring-messaging/src/main/java/org/springframework/messaging/tcp/ReconnectStrategy.java
index daa23943068..54f2f69661b 100644
--- a/spring-messaging/src/main/java/org/springframework/messaging/tcp/ReconnectStrategy.java
+++ b/spring-messaging/src/main/java/org/springframework/messaging/tcp/ReconnectStrategy.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -23,6 +23,7 @@ package org.springframework.messaging.tcp;
  * @author Rossen Stoyanchev
  * @since 4.0
  */
+@FunctionalInterface
 public interface ReconnectStrategy {
 
 	/**
diff --git a/spring-orm/src/main/java/org/springframework/orm/hibernate5/HibernateCallback.java b/spring-orm/src/main/java/org/springframework/orm/hibernate5/HibernateCallback.java
index 54cee881520..d9a836db6d6 100644
--- a/spring-orm/src/main/java/org/springframework/orm/hibernate5/HibernateCallback.java
+++ b/spring-orm/src/main/java/org/springframework/orm/hibernate5/HibernateCallback.java
@@ -30,6 +30,7 @@ import org.hibernate.Session;
  * @see HibernateTemplate
  * @see HibernateTransactionManager
  */
+@FunctionalInterface
 public interface HibernateCallback<T> {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/context/ActiveProfilesResolver.java b/spring-test/src/main/java/org/springframework/test/context/ActiveProfilesResolver.java
index dfefe7d3cb3..bb8efd78f89 100644
--- a/spring-test/src/main/java/org/springframework/test/context/ActiveProfilesResolver.java
+++ b/spring-test/src/main/java/org/springframework/test/context/ActiveProfilesResolver.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -32,6 +32,7 @@ package org.springframework.test.context;
  * @since 4.0
  * @see ActiveProfiles
  */
+@FunctionalInterface
 public interface ActiveProfilesResolver {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/client/RequestMatcher.java b/spring-test/src/main/java/org/springframework/test/web/client/RequestMatcher.java
index 14237729aad..84d53039c00 100644
--- a/spring-test/src/main/java/org/springframework/test/web/client/RequestMatcher.java
+++ b/spring-test/src/main/java/org/springframework/test/web/client/RequestMatcher.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -29,6 +29,7 @@ import org.springframework.http.client.ClientHttpRequest;
  * @author Craig Walls
  * @since 3.2
  */
+@FunctionalInterface
 public interface RequestMatcher {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/client/ResponseCreator.java b/spring-test/src/main/java/org/springframework/test/web/client/ResponseCreator.java
index d7703bc95a5..4b6098a4bcf 100644
--- a/spring-test/src/main/java/org/springframework/test/web/client/ResponseCreator.java
+++ b/spring-test/src/main/java/org/springframework/test/web/client/ResponseCreator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -29,6 +29,7 @@ import org.springframework.test.web.client.response.MockRestResponseCreators;
  * @author Craig Walls
  * @since 3.2
  */
+@FunctionalInterface
 public interface ResponseCreator {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/servlet/ResultHandler.java b/spring-test/src/main/java/org/springframework/test/web/servlet/ResultHandler.java
index ea21c16c4b5..cdb6806b803 100644
--- a/spring-test/src/main/java/org/springframework/test/web/servlet/ResultHandler.java
+++ b/spring-test/src/main/java/org/springframework/test/web/servlet/ResultHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -44,6 +44,7 @@ package org.springframework.test.web.servlet;
  * @author Sam Brannen
  * @since 3.2
  */
+@FunctionalInterface
 public interface ResultHandler {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/servlet/ResultMatcher.java b/spring-test/src/main/java/org/springframework/test/web/servlet/ResultMatcher.java
index f781ba19c08..332019fb822 100644
--- a/spring-test/src/main/java/org/springframework/test/web/servlet/ResultMatcher.java
+++ b/spring-test/src/main/java/org/springframework/test/web/servlet/ResultMatcher.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -46,6 +46,7 @@ package org.springframework.test.web.servlet;
  * @author Sam Brannen
  * @since 3.2
  */
+@FunctionalInterface
 public interface ResultMatcher {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/servlet/htmlunit/WebRequestMatcher.java b/spring-test/src/main/java/org/springframework/test/web/servlet/htmlunit/WebRequestMatcher.java
index 9f34a449de7..5b122ab9028 100644
--- a/spring-test/src/main/java/org/springframework/test/web/servlet/htmlunit/WebRequestMatcher.java
+++ b/spring-test/src/main/java/org/springframework/test/web/servlet/htmlunit/WebRequestMatcher.java
@@ -26,6 +26,7 @@ import com.gargoylesoftware.htmlunit.WebRequest;
  * @see org.springframework.test.web.servlet.htmlunit.HostRequestMatcher
  * @see org.springframework.test.web.servlet.htmlunit.UrlRegexRequestMatcher
  */
+@FunctionalInterface
 public interface WebRequestMatcher {
 
 	/**
diff --git a/spring-test/src/main/java/org/springframework/test/web/servlet/request/RequestPostProcessor.java b/spring-test/src/main/java/org/springframework/test/web/servlet/request/RequestPostProcessor.java
index f531fc07f4f..4dacd88254b 100644
--- a/spring-test/src/main/java/org/springframework/test/web/servlet/request/RequestPostProcessor.java
+++ b/spring-test/src/main/java/org/springframework/test/web/servlet/request/RequestPostProcessor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -32,6 +32,7 @@ import org.springframework.mock.web.MockHttpServletRequest;
  * @author Rob Winch
  * @since 3.2
  */
+@FunctionalInterface
 public interface RequestPostProcessor {
 
 	/**
diff --git a/spring-tx/src/main/java/org/springframework/dao/support/PersistenceExceptionTranslator.java b/spring-tx/src/main/java/org/springframework/dao/support/PersistenceExceptionTranslator.java
index 128b2b15cc0..e8351de2303 100644
--- a/spring-tx/src/main/java/org/springframework/dao/support/PersistenceExceptionTranslator.java
+++ b/spring-tx/src/main/java/org/springframework/dao/support/PersistenceExceptionTranslator.java
@@ -30,6 +30,7 @@ import org.springframework.dao.DataAccessException;
  * @author Juergen Hoeller
  * @since 2.0
  */
+@FunctionalInterface
 public interface PersistenceExceptionTranslator {
 
 	/**
diff --git a/spring-tx/src/main/java/org/springframework/jca/cci/core/ConnectionCallback.java b/spring-tx/src/main/java/org/springframework/jca/cci/core/ConnectionCallback.java
index 3be2710f15c..3729b682e1a 100644
--- a/spring-tx/src/main/java/org/springframework/jca/cci/core/ConnectionCallback.java
+++ b/spring-tx/src/main/java/org/springframework/jca/cci/core/ConnectionCallback.java
@@ -40,6 +40,7 @@ import org.springframework.dao.DataAccessException;
  * @see CciTemplate#execute(javax.resource.cci.InteractionSpec, javax.resource.cci.Record)
  * @see CciTemplate#execute(javax.resource.cci.InteractionSpec, RecordCreator, RecordExtractor)
  */
+@FunctionalInterface
 public interface ConnectionCallback<T> {
 
 	/**
diff --git a/spring-tx/src/main/java/org/springframework/jca/cci/core/InteractionCallback.java b/spring-tx/src/main/java/org/springframework/jca/cci/core/InteractionCallback.java
index 38db29348d5..d480ca71152 100644
--- a/spring-tx/src/main/java/org/springframework/jca/cci/core/InteractionCallback.java
+++ b/spring-tx/src/main/java/org/springframework/jca/cci/core/InteractionCallback.java
@@ -41,6 +41,7 @@ import org.springframework.dao.DataAccessException;
  * @see CciTemplate#execute(javax.resource.cci.InteractionSpec, javax.resource.cci.Record)
  * @see CciTemplate#execute(javax.resource.cci.InteractionSpec, RecordCreator, RecordExtractor)
  */
+@FunctionalInterface
 public interface InteractionCallback<T> {
 
 	/**
diff --git a/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordCreator.java b/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordCreator.java
index f19f6ac2c3d..ce0b57f9386 100644
--- a/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordCreator.java
+++ b/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordCreator.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -45,6 +45,7 @@ import org.springframework.dao.DataAccessException;
  * @see CciTemplate#createMappedRecord(String)
  * @see CciTemplate#setOutputRecordCreator(RecordCreator)
  */
+@FunctionalInterface
 public interface RecordCreator {
 
 	/**
diff --git a/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordExtractor.java b/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordExtractor.java
index 277d8a3cd18..058689707db 100644
--- a/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordExtractor.java
+++ b/spring-tx/src/main/java/org/springframework/jca/cci/core/RecordExtractor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -42,6 +42,7 @@ import org.springframework.dao.DataAccessException;
  * @see CciTemplate#execute(javax.resource.cci.InteractionSpec, RecordCreator, RecordExtractor)
  * @see javax.resource.cci.ResultSet
  */
+@FunctionalInterface
 public interface RecordExtractor<T> {
 
 	/**
diff --git a/spring-tx/src/main/java/org/springframework/transaction/interceptor/TransactionAspectSupport.java b/spring-tx/src/main/java/org/springframework/transaction/interceptor/TransactionAspectSupport.java
index 9eef0e03b23..7795d922107 100644
--- a/spring-tx/src/main/java/org/springframework/transaction/interceptor/TransactionAspectSupport.java
+++ b/spring-tx/src/main/java/org/springframework/transaction/interceptor/TransactionAspectSupport.java
@@ -630,6 +630,7 @@ public abstract class TransactionAspectSupport implements BeanFactoryAware, Init
 	 * Simple callback interface for proceeding with the target invocation.
 	 * Concrete interceptors/aspects adapt this to their invocation mechanism.
 	 */
+	@FunctionalInterface
 	protected interface InvocationCallback {
 
 		Object proceedWithInvocation() throws Throwable;
diff --git a/spring-tx/src/main/java/org/springframework/transaction/support/TransactionCallback.java b/spring-tx/src/main/java/org/springframework/transaction/support/TransactionCallback.java
index 80e8bde72a1..8e298d00811 100644
--- a/spring-tx/src/main/java/org/springframework/transaction/support/TransactionCallback.java
+++ b/spring-tx/src/main/java/org/springframework/transaction/support/TransactionCallback.java
@@ -32,6 +32,7 @@ import org.springframework.transaction.TransactionStatus;
  * @see TransactionTemplate
  * @see CallbackPreferringPlatformTransactionManager
  */
+@FunctionalInterface
 public interface TransactionCallback<T> {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/http/StreamingHttpOutputMessage.java b/spring-web/src/main/java/org/springframework/http/StreamingHttpOutputMessage.java
index 66facbb588c..abe13051bfa 100644
--- a/spring-web/src/main/java/org/springframework/http/StreamingHttpOutputMessage.java
+++ b/spring-web/src/main/java/org/springframework/http/StreamingHttpOutputMessage.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -41,6 +41,7 @@ public interface StreamingHttpOutputMessage extends HttpOutputMessage {
 	 * It is useful with HTTP client libraries that provide indirect access to an
 	 * {@link OutputStream} via a callback mechanism.
 	 */
+	@FunctionalInterface
 	interface Body {
 
 		/**
diff --git a/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestExecution.java b/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestExecution.java
index df6e10c6f0e..d3568341223 100644
--- a/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestExecution.java
+++ b/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestExecution.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2011 the original author or authors.
+ * Copyright 2002-2016 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.http.HttpRequest;
  * @see ClientHttpRequestInterceptor
  * @since 3.1
  */
+@FunctionalInterface
 public interface ClientHttpRequestExecution {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestFactory.java b/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestFactory.java
index 4a2a502e1a8..9ca49a8da42 100644
--- a/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestFactory.java
+++ b/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestFactory.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,6 +28,7 @@ import org.springframework.http.HttpMethod;
  * @author Arjen Poutsma
  * @since 3.0
  */
+@FunctionalInterface
 public interface ClientHttpRequestFactory {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestInterceptor.java b/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestInterceptor.java
index 410cdeb2ff6..4788d879d81 100644
--- a/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestInterceptor.java
+++ b/spring-web/src/main/java/org/springframework/http/client/ClientHttpRequestInterceptor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2012 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -31,6 +31,7 @@ import org.springframework.http.HttpRequest;
  * @author Arjen Poutsma
  * @since 3.1
  */
+@FunctionalInterface
 public interface ClientHttpRequestInterceptor {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/remoting/httpinvoker/HttpInvokerRequestExecutor.java b/spring-web/src/main/java/org/springframework/remoting/httpinvoker/HttpInvokerRequestExecutor.java
index 433edd83105..24afc47a543 100644
--- a/spring-web/src/main/java/org/springframework/remoting/httpinvoker/HttpInvokerRequestExecutor.java
+++ b/spring-web/src/main/java/org/springframework/remoting/httpinvoker/HttpInvokerRequestExecutor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -41,6 +41,7 @@ import org.springframework.remoting.support.RemoteInvocationResult;
  * @since 1.1
  * @see HttpInvokerClientInterceptor#setHttpInvokerRequestExecutor
  */
+@FunctionalInterface
 public interface HttpInvokerRequestExecutor {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/HttpRequestHandler.java b/spring-web/src/main/java/org/springframework/web/HttpRequestHandler.java
index 2e259e93861..ac173879a68 100644
--- a/spring-web/src/main/java/org/springframework/web/HttpRequestHandler.java
+++ b/spring-web/src/main/java/org/springframework/web/HttpRequestHandler.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -74,6 +74,7 @@ import javax.servlet.http.HttpServletResponse;
  * @see org.springframework.remoting.caucho.HessianServiceExporter
  * @see org.springframework.remoting.caucho.BurlapServiceExporter
  */
+@FunctionalInterface
 public interface HttpRequestHandler {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/accept/ContentNegotiationStrategy.java b/spring-web/src/main/java/org/springframework/web/accept/ContentNegotiationStrategy.java
index 586485a72a2..6f998e73c4c 100644
--- a/spring-web/src/main/java/org/springframework/web/accept/ContentNegotiationStrategy.java
+++ b/spring-web/src/main/java/org/springframework/web/accept/ContentNegotiationStrategy.java
@@ -28,6 +28,7 @@ import org.springframework.web.context.request.NativeWebRequest;
  * @author Rossen Stoyanchev
  * @since 3.2
  */
+@FunctionalInterface
 public interface ContentNegotiationStrategy {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/bind/support/WebArgumentResolver.java b/spring-web/src/main/java/org/springframework/web/bind/support/WebArgumentResolver.java
index 4fcc9c2e0b5..5887d32c41e 100644
--- a/spring-web/src/main/java/org/springframework/web/bind/support/WebArgumentResolver.java
+++ b/spring-web/src/main/java/org/springframework/web/bind/support/WebArgumentResolver.java
@@ -41,6 +41,7 @@ import org.springframework.web.context.request.NativeWebRequest;
  * @since 2.5.2
  * @see org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter#setCustomArgumentResolvers
  */
+@FunctionalInterface
 public interface WebArgumentResolver {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/client/AsyncRequestCallback.java b/spring-web/src/main/java/org/springframework/web/client/AsyncRequestCallback.java
index 4a9840ef596..5dae560cbe2 100644
--- a/spring-web/src/main/java/org/springframework/web/client/AsyncRequestCallback.java
+++ b/spring-web/src/main/java/org/springframework/web/client/AsyncRequestCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2013 the original author or authors.
+ * Copyright 2002-2016 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.http.client.AsyncClientHttpRequest;
  * @see org.springframework.web.client.AsyncRestTemplate#execute
  * @since 4.0
  */
+@FunctionalInterface
 public interface AsyncRequestCallback {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/client/RequestCallback.java b/spring-web/src/main/java/org/springframework/web/client/RequestCallback.java
index a6474a73093..9c4f3dff2d6 100644
--- a/spring-web/src/main/java/org/springframework/web/client/RequestCallback.java
+++ b/spring-web/src/main/java/org/springframework/web/client/RequestCallback.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2016 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.http.client.ClientHttpRequest;
  * @see RestTemplate#execute
  * @since 3.0
  */
+@FunctionalInterface
 public interface RequestCallback {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/client/ResponseExtractor.java b/spring-web/src/main/java/org/springframework/web/client/ResponseExtractor.java
index 2a0d9f6e455..143fb6925f2 100644
--- a/spring-web/src/main/java/org/springframework/web/client/ResponseExtractor.java
+++ b/spring-web/src/main/java/org/springframework/web/client/ResponseExtractor.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2009 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -32,6 +32,7 @@ import org.springframework.http.client.ClientHttpResponse;
  * @since 3.0
  * @see RestTemplate#execute
  */
+@FunctionalInterface
 public interface ResponseExtractor<T> {
 
 	/**
diff --git a/spring-web/src/main/java/org/springframework/web/context/request/async/DeferredResult.java b/spring-web/src/main/java/org/springframework/web/context/request/async/DeferredResult.java
index 5ce98714913..dc72b00cb3a 100644
--- a/spring-web/src/main/java/org/springframework/web/context/request/async/DeferredResult.java
+++ b/spring-web/src/main/java/org/springframework/web/context/request/async/DeferredResult.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -243,6 +243,7 @@ public class DeferredResult<T> {
 	/**
 	 * Handles a DeferredResult value when set.
 	 */
+	@FunctionalInterface
 	public interface DeferredResultHandler {
 
 		void handleResult(Object result);
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/handler/HandlerMethodMappingNamingStrategy.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/handler/HandlerMethodMappingNamingStrategy.java
index f764b182b57..fb38cd5f27c 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/handler/HandlerMethodMappingNamingStrategy.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/handler/HandlerMethodMappingNamingStrategy.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -37,6 +37,7 @@ import org.springframework.web.method.HandlerMethod;
  * @author Rossen Stoyanchev
  * @since 4.1
  */
+@FunctionalInterface
 public interface HandlerMethodMappingNamingStrategy<T> {
 
 	/**
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/Controller.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/Controller.java
index 702ab7ccd9c..f4f6bc88d77 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/Controller.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/Controller.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2014 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -106,6 +106,7 @@ import org.springframework.web.servlet.ModelAndView;
  * @see org.springframework.web.context.ServletContextAware
  * @see org.springframework.web.context.support.WebApplicationObjectSupport
  */
+@FunctionalInterface
 public interface Controller {
 
 	/**
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ResponseBodyEmitterAdapter.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ResponseBodyEmitterAdapter.java
index fc827cc20a5..da1e91ca0d8 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ResponseBodyEmitterAdapter.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/ResponseBodyEmitterAdapter.java
@@ -24,6 +24,7 @@ import org.springframework.http.server.ServerHttpResponse;
  * @author Rossen Stoyanchev
  * @since 4.3
  */
+@FunctionalInterface
 public interface ResponseBodyEmitterAdapter {
 
 	/**
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/StreamingResponseBody.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/StreamingResponseBody.java
index a3a4240c205..a75a135a307 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/StreamingResponseBody.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/mvc/method/annotation/StreamingResponseBody.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -35,6 +35,7 @@ import java.io.OutputStream;
  * @author Rossen Stoyanchev
  * @since 4.2
  */
+@FunctionalInterface
 public interface StreamingResponseBody {
 
 	/**
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/AppCacheManifestTransformer.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/AppCacheManifestTransformer.java
index aa07717842d..7e0e0591646 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/AppCacheManifestTransformer.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/AppCacheManifestTransformer.java
@@ -143,7 +143,8 @@ public class AppCacheManifestTransformer extends ResourceTransformerSupport {
 	}
 
 
-	private static interface SectionTransformer {
+	@FunctionalInterface
+	private interface SectionTransformer {
 
 		/**
 		 * Transforms a line in a section of the manifest.
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/CssLinkResourceTransformer.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/CssLinkResourceTransformer.java
index b0fc201c19d..e335c76e68a 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/CssLinkResourceTransformer.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/CssLinkResourceTransformer.java
@@ -128,7 +128,8 @@ public class CssLinkResourceTransformer extends ResourceTransformerSupport {
 	}
 
 
-	protected static interface CssLinkParser {
+	@FunctionalInterface
+	protected interface CssLinkParser {
 
 		void parseLink(String content, Set<CssLinkInfo> linkInfos);
 
diff --git a/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/ResourceTransformer.java b/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/ResourceTransformer.java
index fe941d830bf..a9e2a7346b5 100644
--- a/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/ResourceTransformer.java
+++ b/spring-webmvc/src/main/java/org/springframework/web/servlet/resource/ResourceTransformer.java
@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -28,6 +28,7 @@ import org.springframework.core.io.Resource;
  * @author Rossen Stoyanchev
  * @since 4.1
  */
+@FunctionalInterface
 public interface ResourceTransformer {
 
 	/**