Java tutorial
/* * ==================================================================== * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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. * ==================================================================== * * This software consists of voluntary contributions made by many * individuals on behalf of the Apache Software Foundation. For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package interoperabilite.webservice.client; import java.io.IOException; import java.util.concurrent.CancellationException; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.TimeUnit; import org.apache.http.HttpResponse; import org.apache.http.client.ClientProtocolException; import org.apache.http.client.HttpClient; import org.apache.http.client.ResponseHandler; import org.apache.http.client.methods.HttpGet; import org.apache.http.client.protocol.HttpClientContext; import org.apache.http.concurrent.FutureCallback; import org.apache.http.impl.client.FutureRequestExecutionService; import org.apache.http.impl.client.HttpClientBuilder; import org.apache.http.impl.client.HttpRequestFutureTask; public class ClientWithRequestFuture { public static void main(String[] args) throws Exception { // the simplest way to create a HttpAsyncClientWithFuture HttpClient httpclient = HttpClientBuilder.create().setMaxConnPerRoute(5).setMaxConnTotal(5).build(); ExecutorService execService = Executors.newFixedThreadPool(5); FutureRequestExecutionService requestExecService = new FutureRequestExecutionService(httpclient, execService); try { // Because things are asynchronous, you must provide a ResponseHandler ResponseHandler<Boolean> handler = new ResponseHandler<Boolean>() { @Override public Boolean handleResponse(HttpResponse response) throws ClientProtocolException, IOException { // simply return true if the status was OK return response.getStatusLine().getStatusCode() == 200; } }; // Simple request ... HttpGet request1 = new HttpGet("http://httpbin.org/get"); HttpRequestFutureTask<Boolean> futureTask1 = requestExecService.execute(request1, HttpClientContext.create(), handler); Boolean wasItOk1 = futureTask1.get(); System.out.println("It was ok? " + wasItOk1); // Cancel a request try { HttpGet request2 = new HttpGet("http://httpbin.org/get"); HttpRequestFutureTask<Boolean> futureTask2 = requestExecService.execute(request2, HttpClientContext.create(), handler); futureTask2.cancel(true); Boolean wasItOk2 = futureTask2.get(); System.out.println("It was cancelled so it should never print this: " + wasItOk2); } catch (CancellationException e) { System.out.println("We cancelled it, so this is expected"); } // Request with a timeout HttpGet request3 = new HttpGet("http://httpbin.org/get"); HttpRequestFutureTask<Boolean> futureTask3 = requestExecService.execute(request3, HttpClientContext.create(), handler); Boolean wasItOk3 = futureTask3.get(10, TimeUnit.SECONDS); System.out.println("It was ok? " + wasItOk3); FutureCallback<Boolean> callback = new FutureCallback<Boolean>() { @Override public void completed(Boolean result) { System.out.println("completed with " + result); } @Override public void failed(Exception ex) { System.out.println("failed with " + ex.getMessage()); } @Override public void cancelled() { System.out.println("cancelled"); } }; // Simple request with a callback HttpGet request4 = new HttpGet("http://httpbin.org/get"); // using a null HttpContext here since it is optional // the callback will be called when the task completes, fails, or is cancelled HttpRequestFutureTask<Boolean> futureTask4 = requestExecService.execute(request4, HttpClientContext.create(), handler, callback); Boolean wasItOk4 = futureTask4.get(10, TimeUnit.SECONDS); System.out.println("It was ok? " + wasItOk4); } finally { requestExecService.close(); } } }