Apache HttpComponents 多线程处理HTTP请求

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*      http://www.apache.org/licenses/LICENSE-2.0
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*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation.  For more
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package org.apache.http.examples.client;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.impl.conn.PoolingClientConnectionManager;
import org.apache.http.protocol.BasicHttpContext;
import org.apache.http.protocol.HttpContext;
import org.apache.http.util.EntityUtils;
/**
* An example that performs GETs from multiple threads.
*
*/
public class ClientMultiThreadedExecution {
public static void main(String[] args) throws Exception {
// Create an HttpClient with the ThreadSafeClientConnManager.
// This connection manager must be used if more than one thread will
// be using the HttpClient.
PoolingClientConnectionManager cm = new PoolingClientConnectionManager();
cm.setMaxTotal(100);
HttpClient httpclient = new DefaultHttpClient(cm);
try {
// create an array of URIs to perform GETs on
String[] urisToGet = {
"http://hc.apache.org/",
"http://hc.apache.org/httpcomponents-core-ga/",
"http://hc.apache.org/httpcomponents-client-ga/",
"http://svn.apache.org/viewvc/httpcomponents/"
};
// create a thread for each URI
GetThread[] threads = new GetThread[urisToGet.length];
for (int i = 0; i < threads.length; i++) {
HttpGet httpget = new HttpGet(urisToGet);
threads = new GetThread(httpclient, httpget, i + 1);
}
// start the threads
for (int j = 0; j < threads.length; j++) {
threads[j].start();
}
// join the threads
for (int j = 0; j < threads.length; j++) {
threads[j].join();
}
} finally {
// When HttpClient instance is no longer needed,
// shut down the connection manager to ensure
// immediate deallocation of all system resources
            httpclient.getConnectionManager().shutdown();
}
}
/**
* A thread that performs a GET.
*/
static class GetThread extends Thread {
private final HttpClient httpClient;
private final HttpContext context;
private final HttpGet httpget;
private final int id;
public GetThread(HttpClient httpClient, HttpGet httpget, int id) {
this.httpClient = httpClient;
this.context = new BasicHttpContext();
this.httpget = httpget;
this.id = id;
}
/**
* Executes the GetMethod and prints some status information.
*/
@Override
public void run() {
System.out.println(id + " - about to get something from " + httpget.getURI());
try {
// execute the method
HttpResponse response = httpClient.execute(httpget, context);
System.out.println(id + " - get executed");
// get the response body as an array of bytes
HttpEntity entity = response.getEntity();
if (entity != null) {
byte[] bytes = EntityUtils.toByteArray(entity);
System.out.println(id + " - " + bytes.length + " bytes read");
}
} catch (Exception e) {
httpget.abort();
System.out.println(id + " - error: " + e);
}
}
}
}