Make HttpComponentsAsyncClientHttpRequest abortable

This commit aborts the HttpComponentsAsyncClientHttpRequest whenever the
returned Future is canceled.

Issue: SPR-14845
(cherry picked from commit 8f84446)

spring-web/src/main/java/org/springframework/http/client/HttpComponentsAsyncClientHttpRequest.java

@@ -92,7 +92,7 @@ final class HttpComponentsAsyncClientHttpRequest extends AbstractBufferingAsyncC
 			entityEnclosingRequest.setEntity(requestEntity);
 		}
 
-		final HttpResponseFutureCallback callback = new HttpResponseFutureCallback();
+		final HttpResponseFutureCallback callback = new HttpResponseFutureCallback(this.httpRequest);
 		final Future<HttpResponse> futureResponse =
 				this.httpClient.execute(this.httpRequest, this.httpContext, callback);
 		return new ClientHttpResponseFuture(futureResponse, callback);
@@ -101,9 +101,15 @@ final class HttpComponentsAsyncClientHttpRequest extends AbstractBufferingAsyncC
 
 	private static class HttpResponseFutureCallback implements FutureCallback<HttpResponse> {
 
+		private final HttpUriRequest httpRequest;
+
 		private final ListenableFutureCallbackRegistry<ClientHttpResponse> callbacks =
 				new ListenableFutureCallbackRegistry<ClientHttpResponse>();
 
+		public HttpResponseFutureCallback(HttpUriRequest httpRequest) {
+			this.httpRequest = httpRequest;
+		}
+
 		public void addCallback(ListenableFutureCallback<? super ClientHttpResponse> callback) {
 			this.callbacks.addCallback(callback);
 		}
@@ -128,6 +134,7 @@ final class HttpComponentsAsyncClientHttpRequest extends AbstractBufferingAsyncC
 
 		@Override
 		public void cancelled() {
+			this.httpRequest.abort();
 		}
 	}
 

spring-web/src/test/java/org/springframework/http/client/AbstractAsyncHttpRequestFactoryTestCase.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.
@@ -222,4 +222,14 @@ public abstract class AbstractAsyncHttpRequestFactoryTestCase extends AbstractJe
 		}
 	}
 
+	@Test
+	public void cancel() throws Exception {
+		URI uri = new URI(baseUrl + "/status/notfound");
+		AsyncClientHttpRequest request = this.factory.createAsyncRequest(uri, HttpMethod.GET);
+		Future<ClientHttpResponse> futureResponse = request.executeAsync();
+		futureResponse.cancel(true);
+		assertTrue(futureResponse.isCancelled());
+	}
+
+
 }