Add ServerHttpResponseDecorator

For completeness and consistency with the existing
ServerHttpRequestDecorator and the ServerWebExchangeDecorator.

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

@@ -39,7 +39,7 @@ public class ServerHttpRequestDecorator implements ServerHttpRequest {
 
 
 	public ServerHttpRequestDecorator(ServerHttpRequest delegate) {
-		Assert.notNull(delegate, "'delegate' is required.");
+		Assert.notNull(delegate, "ServerHttpRequest delegate is required.");
 		this.delegate = delegate;
 	}
 

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

@@ -0,0 +1,112 @@
+/*
+ * 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.
+ * 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 java.util.function.Function;
+import java.util.function.Supplier;
+
+import org.reactivestreams.Publisher;
+import reactor.core.publisher.Mono;
+
+import org.springframework.core.io.buffer.DataBuffer;
+import org.springframework.core.io.buffer.DataBufferFactory;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseCookie;
+import org.springframework.util.Assert;
+import org.springframework.util.MultiValueMap;
+
+/**
+ * Wraps another {@link ServerHttpResponse} and delegates all methods to it.
+ * Sub-classes can override specific methods selectively.
+ *
+ * @author Rossen Stoyanchev
+ * @since 5.0
+ */
+public class ServerHttpResponseDecorator implements ServerHttpResponse {
+
+	private final ServerHttpResponse delegate;
+
+
+	public ServerHttpResponseDecorator(ServerHttpResponse delegate) {
+		Assert.notNull(delegate, "ServerHttpResponse delegate is required.");
+		this.delegate = delegate;
+	}
+
+
+	public ServerHttpResponse getDelegate() {
+		return this.delegate;
+	}
+
+
+	// ServerHttpResponse delegation methods...
+
+	@Override
+	public boolean setStatusCode(HttpStatus status) {
+		return getDelegate().setStatusCode(status);
+	}
+
+	@Override
+	public HttpStatus getStatusCode() {
+		return getDelegate().getStatusCode();
+	}
+
+	@Override
+	public HttpHeaders getHeaders() {
+		return getDelegate().getHeaders();
+	}
+
+	@Override
+	public MultiValueMap<String, ResponseCookie> getCookies() {
+		return getDelegate().getCookies();
+	}
+
+	@Override
+	public String encodeUrl(String url) {
+		return getDelegate().encodeUrl(url);
+	}
+
+	@Override
+	public void registerUrlEncoder(Function<String, String> encoder) {
+		getDelegate().registerUrlEncoder(encoder);
+	}
+
+	@Override
+	public DataBufferFactory bufferFactory() {
+		return getDelegate().bufferFactory();
+	}
+
+	@Override
+	public void beforeCommit(Supplier<? extends Mono<Void>> action) {
+		getDelegate().beforeCommit(action);
+	}
+
+	@Override
+	public Mono<Void> writeWith(Publisher<? extends DataBuffer> body) {
+		return getDelegate().writeWith(body);
+	}
+
+	@Override
+	public Mono<Void> writeAndFlushWith(Publisher<? extends Publisher<? extends DataBuffer>> body) {
+		return getDelegate().writeAndFlushWith(body);
+	}
+
+	@Override
+	public Mono<Void> setComplete() {
+		return getDelegate().setComplete();
+	}
+
+}