Add HttpHandlerDecorator and fix test package

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/FilterChainHttpHandler.java

@@ -21,7 +21,6 @@ import java.util.List;
 
 import org.reactivestreams.Publisher;
 
-import org.springframework.util.Assert;
 
 /**
  * {@link HttpHandler} that delegates to a chain of {@link HttpFilter}s followed
@@ -29,17 +28,14 @@ import org.springframework.util.Assert;
  *
  * @author Rossen Stoyanchev
  */
-public class FilterChainHttpHandler implements HttpHandler {
+public class FilterChainHttpHandler extends HttpHandlerDecorator {
 
 	private final List<HttpFilter> filters;
 
-	private final HttpHandler targetHandler;
-
 
 	public FilterChainHttpHandler(HttpHandler targetHandler, HttpFilter... filters) {
-		Assert.notNull(targetHandler, "'targetHandler' is required.");
+		super(targetHandler);
 		this.filters = (filters != null ? Arrays.asList(filters) : Collections.emptyList());
-		this.targetHandler = targetHandler;
 	}
 
 
@@ -60,7 +56,7 @@ public class FilterChainHttpHandler implements HttpHandler {
 				return filter.filter(request, response, this);
 			}
 			else {
-				return targetHandler.handle(request, response);
+				return getDelegate().handle(request, response);
 			}
 		}
 	}

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/HttpHandlerDecorator.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright 2002-2015 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
+ *
+ *      http://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.http.server.reactive;
+
+import org.reactivestreams.Publisher;
+
+import org.springframework.util.Assert;
+
+/**
+ *
+ * @author Rossen Stoyanchev
+ */
+public class HttpHandlerDecorator implements HttpHandler {
+
+	private final HttpHandler delegate;
+
+
+	public HttpHandlerDecorator(HttpHandler delegate) {
+		Assert.notNull(delegate, "'delegate' must not be null");
+		this.delegate = delegate;
+	}
+
+
+	public HttpHandler getDelegate() {
+		return this.delegate;
+	}
+
+
+	@Override
+	public Publisher<Void> handle(ServerHttpRequest request, ServerHttpResponse response) {
+		return this.delegate.handle(request, response);
+	}
+
+	@Override
+	public String toString() {
+		return getClass().getSimpleName() + " [delegate=" + this.delegate + "]";
+	}
+
+}