/*
* $HeadURL: http://svn.apache.org/repos/asf/httpcomponents/httpcore/tags/4.0/module-nio/src/examples/org/apache/http/examples/nio/NHttpClient.java $
* $Revision: 744516 $
* $Date: 2009-02-14 17:38:14 +0100 (Sat, 14 Feb 2009) $
*
* ====================================================================
* 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 org.apache.http.examples.nio;
import java.io.IOException;
import java.io.InterruptedIOException;
import java.net.InetSocketAddress;
import java.util.concurrent.CountDownLatch;
import org.apache.http.HttpEntity;
import org.apache.http.HttpException;
import org.apache.http.HttpHost;
import org.apache.http.HttpRequest;
import org.apache.http.HttpResponse;
import org.apache.http.impl.DefaultConnectionReuseStrategy;
import org.apache.http.params.BasicHttpParams;
import org.apache.http.impl.nio.DefaultClientIOEventDispatch;
import org.apache.http.impl.nio.reactor.DefaultConnectingIOReactor;
import org.apache.http.message.BasicHttpRequest;
import org.apache.http.nio.NHttpConnection;
import org.apache.http.nio.protocol.BufferingHttpClientHandler;
import org.apache.http.nio.protocol.EventListener;
import org.apache.http.nio.protocol.HttpRequestExecutionHandler;
import org.apache.http.nio.reactor.ConnectingIOReactor;
import org.apache.http.nio.reactor.IOEventDispatch;
import org.apache.http.nio.reactor.SessionRequest;
import org.apache.http.nio.reactor.SessionRequestCallback;
import org.apache.http.params.CoreConnectionPNames;
import org.apache.http.params.HttpParams;
import org.apache.http.params.CoreProtocolPNames;
import org.apache.http.protocol.BasicHttpProcessor;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.ExecutionContext;
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;
import org.apache.http.util.EntityUtils;
/**
* Elemental example for executing HTTP requests using the non-blocking I/O model.
* <p>
* Please note the purpose of this application is demonstrate the usage of HttpCore APIs.
* It is NOT intended to demonstrate the most efficient way of building an HTTP client.
*
*
* @version $Revision: 744516 $
*/
public class NHttpClient {
public static void main(String[] args) throws Exception {
HttpParams params = new BasicHttpParams();
params
.setIntParameter(CoreConnectionPNames.SO_TIMEOUT, 5000)
.setIntParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000)
.setIntParameter(CoreConnectionPNames.SOCKET_BUFFER_SIZE, 8 * 1024)
.setBooleanParameter(CoreConnectionPNames.STALE_CONNECTION_CHECK, false)
.setBooleanParameter(CoreConnectionPNames.TCP_NODELAY, true)
.setParameter(CoreProtocolPNames.USER_AGENT, "HttpComponents/1.1");
final ConnectingIOReactor ioReactor = new DefaultConnectingIOReactor(2, params);
BasicHttpProcessor httpproc = new BasicHttpProcessor();
httpproc.addInterceptor(new RequestContent());
httpproc.addInterceptor(new RequestTargetHost());
httpproc.addInterceptor(new RequestConnControl());
httpproc.addInterceptor(new RequestUserAgent());
httpproc.addInterceptor(new RequestExpectContinue());
// We are going to use this object to synchronize between the
// I/O event and main threads
CountDownLatch requestCount = new CountDownLatch(3);
BufferingHttpClientHandler handler = new BufferingHttpClientHandler(
httpproc,
new MyHttpRequestExecutionHandler(requestCount),
new DefaultConnectionReuseStrategy(),
params);
handler.setEventListener(new EventLogger());
final IOEventDispatch ioEventDispatch = new DefaultClientIOEventDispatch(handler, params);
Thread t = new Thread(new Runnable() {
public void run() {
try {
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");
}
});
t.start();
SessionRequest[] reqs = new SessionRequest[3];
reqs[0] = ioReactor.connect(
new InetSocketAddress("www.yahoo.com", 80),
null,
new HttpHost("www.yahoo.com"),
new MySessionRequestCallback(requestCount));
reqs[1] = ioReactor.connect(
new InetSocketAddress("www.google.com", 80),
null,
new HttpHost("www.google.ch"),
new MySessionRequestCallback(requestCount));
reqs[2] = ioReactor.connect(
new InetSocketAddress("www.apache.org", 80),
null,
new HttpHost("www.apache.org"),
new MySessionRequestCallback(requestCount));
// Block until all connections signal
// completion of the request execution
requestCount.await();
System.out.println("Shutting down I/O reactor");
ioReactor.shutdown();
System.out.println("Done");
}
static class MyHttpRequestExecutionHandler implements HttpRequestExecutionHandler {
private final static String REQUEST_SENT = "request-sent";
private final static String RESPONSE_RECEIVED = "response-received";
private final CountDownLatch requestCount;
public MyHttpRequestExecutionHandler(final CountDownLatch requestCount) {
super();
this.requestCount = requestCount;
}
public void initalizeContext(final HttpContext context, final Object attachment) {
HttpHost targetHost = (HttpHost) attachment;
context.setAttribute(ExecutionContext.HTTP_TARGET_HOST, targetHost);
}
public void finalizeContext(final HttpContext context) {
Object flag = context.getAttribute(RESPONSE_RECEIVED);
if (flag == null) {
// Signal completion of the request execution
requestCount.countDown();
}
}
public HttpRequest submitRequest(final HttpContext context) {
HttpHost targetHost = (HttpHost) context.getAttribute(
ExecutionContext.HTTP_TARGET_HOST);
Object flag = context.getAttribute(REQUEST_SENT);
if (flag == null) {
// Stick some object into the context
context.setAttribute(REQUEST_SENT, Boolean.TRUE);
System.out.println("--------------");
System.out.println("Sending request to " + targetHost);
System.out.println("--------------");
return new BasicHttpRequest("GET", "/");
} else {
// No new request to submit
return null;
}
}
public void handleResponse(final HttpResponse response, final HttpContext context) {
HttpEntity entity = response.getEntity();
try {
String content = EntityUtils.toString(entity);
System.out.println("--------------");
System.out.println(response.getStatusLine());
System.out.println("--------------");
System.out.println("Document length: " + content.length());
System.out.println("--------------");
} catch (IOException ex) {
System.err.println("I/O error: " + ex.getMessage());
}
context.setAttribute(RESPONSE_RECEIVED, Boolean.TRUE);
// Signal completion of the request execution
requestCount.countDown();
}
}
static class MySessionRequestCallback implements SessionRequestCallback {
private final CountDownLatch requestCount;
public MySessionRequestCallback(final CountDownLatch requestCount) {
super();
this.requestCount = requestCount;
}
public void cancelled(final SessionRequest request) {
System.out.println("Connect request cancelled: " + request.getRemoteAddress());
this.requestCount.countDown();
}
public void completed(final SessionRequest request) {
}
public void failed(final SessionRequest request) {
System.out.println("Connect request failed: " + request.getRemoteAddress());
this.requestCount.countDown();
}
public void timeout(final SessionRequest request) {
System.out.println("Connect request timed out: " + request.getRemoteAddress());
this.requestCount.countDown();
}
}
static class EventLogger implements EventListener {
public void connectionOpen(final NHttpConnection conn) {
System.out.println("Connection open: " + conn);
}
public void connectionTimeout(final NHttpConnection conn) {
System.out.println("Connection timed out: " + conn);
}
public void connectionClosed(final NHttpConnection conn) {
System.out.println("Connection closed: " + conn);
}
public void fatalIOException(final IOException ex, final NHttpConnection conn) {
System.err.println("I/O error: " + ex.getMessage());
}
public void fatalProtocolException(final HttpException ex, final NHttpConnection conn) {
System.err.println("HTTP error: " + ex.getMessage());
}
}
}