Java tutorial
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For more * information on the Apache Software Foundation, please see * <http://www.apache.org/>. * */ package com.yulore.demo; import java.io.IOException; import java.io.InterruptedIOException; import java.util.concurrent.CountDownLatch; import org.apache.http.HttpHost; import org.apache.http.HttpResponse; import org.apache.http.concurrent.FutureCallback; import org.apache.http.config.ConnectionConfig; import org.apache.http.impl.nio.DefaultHttpClientIODispatch; import org.apache.http.impl.nio.pool.BasicNIOConnPool; import org.apache.http.impl.nio.reactor.DefaultConnectingIOReactor; import org.apache.http.message.BasicHttpRequest; import org.apache.http.nio.protocol.BasicAsyncRequestProducer; import org.apache.http.nio.protocol.BasicAsyncResponseConsumer; import org.apache.http.nio.protocol.HttpAsyncRequestExecutor; import org.apache.http.nio.protocol.HttpAsyncRequester; import org.apache.http.nio.reactor.ConnectingIOReactor; import org.apache.http.nio.reactor.IOEventDispatch; import org.apache.http.protocol.HttpCoreContext; import org.apache.http.protocol.HttpProcessor; import org.apache.http.protocol.HttpProcessorBuilder; import org.apache.http.protocol.RequestConnControl; import org.apache.http.protocol.RequestContent; import org.apache.http.protocol.RequestExpectContinue; import org.apache.http.protocol.RequestTargetHost; import org.apache.http.protocol.RequestUserAgent; /** * Minimal asynchronous HTTP/1.1 client. * <p/> * Please note that this example represents a minimal HTTP client implementation. * It does not support HTTPS as is. * You either need to provide BasicNIOConnPool with a connection factory * that supports SSL or use a more complex HttpAsyncClient. * * @see BasicNIOConnPool#BasicNIOConnPool(org.apache.http.nio.reactor.ConnectingIOReactor, * org.apache.http.nio.pool.NIOConnFactory, int) * @see org.apache.http.impl.nio.pool.BasicNIOConnFactory */ public class NHttpClient { public static void main(String[] args) throws Exception { // Create HTTP protocol processing chain HttpProcessor httpproc = HttpProcessorBuilder.create() // Use standard client-side protocol interceptors .add(new RequestContent()).add(new RequestTargetHost()).add(new RequestConnControl()) .add(new RequestUserAgent("Test/1.1")).add(new RequestExpectContinue(true)).build(); // Create client-side HTTP protocol handler HttpAsyncRequestExecutor protocolHandler = new HttpAsyncRequestExecutor(); // Create client-side I/O event dispatch final IOEventDispatch ioEventDispatch = new DefaultHttpClientIODispatch(protocolHandler, ConnectionConfig.DEFAULT); // Create client-side I/O reactor final ConnectingIOReactor ioReactor = new DefaultConnectingIOReactor(); // Create HTTP connection pool BasicNIOConnPool pool = new BasicNIOConnPool(ioReactor, ConnectionConfig.DEFAULT); // Limit total number of connections to just two pool.setDefaultMaxPerRoute(2); pool.setMaxTotal(2); // Run the I/O reactor in a separate thread Thread t = new Thread(new Runnable() { public void run() { try { // Ready to go! ioReactor.execute(ioEventDispatch); } catch (InterruptedIOException ex) { System.err.println("Interrupted"); } catch (IOException e) { System.err.println("I/O error: " + e.getMessage()); } System.out.println("Shutdown"); } }); // Start the client thread t.start(); // Create HTTP requester HttpAsyncRequester requester = new HttpAsyncRequester(httpproc); // Execute HTTP GETs to the following hosts and HttpHost[] targets = new HttpHost[] { new HttpHost("www.apache.org", 80, "http"), new HttpHost("www.verisign.com", 443, "https"), new HttpHost("www.google.com", 80, "http") }; final CountDownLatch latch = new CountDownLatch(targets.length); for (final HttpHost target : targets) { BasicHttpRequest request = new BasicHttpRequest("GET", "/"); HttpCoreContext coreContext = HttpCoreContext.create(); requester.execute(new BasicAsyncRequestProducer(target, request), new BasicAsyncResponseConsumer(), pool, coreContext, // Handle HTTP response from a callback new FutureCallback<HttpResponse>() { public void completed(final HttpResponse response) { latch.countDown(); System.out.println(target + "->" + response.getStatusLine()); } public void failed(final Exception ex) { latch.countDown(); System.out.println(target + "->" + ex); } public void cancelled() { latch.countDown(); System.out.println(target + " cancelled"); } }); } latch.await(); System.out.println("Shutting down I/O reactor"); ioReactor.shutdown(); System.out.println("Done"); } }