多线程施用httpclient

多线程使用httpclient

public class ClientMultiThreadedExecution {

    public static void main(String[] args) throws Exception {
        // Create and initialize HTTP parameters
        HttpParams params = new BasicHttpParams();
        ConnManagerParams.setMaxTotalConnections(params, 100);
        HttpProtocolParams.setVersion(params, HttpVersion.HTTP_1_1);

        // Create and initialize scheme registry
        SchemeRegistry schemeRegistry = new SchemeRegistry();
        schemeRegistry.register(
                new Scheme("http", PlainSocketFactory.getSocketFactory(), 80));

        // Create an HttpClient with the ThreadSafeClientConnManager.
        // This connection manager must be used if more than one thread will
        // be using the HttpClient.
        ClientConnectionManager cm = new ThreadSafeClientConnManager(params, schemeRegistry);
        HttpClient httpClient = new DefaultHttpClient(cm, params);

        // create an array of URIs to perform GETs on
        String[] urisToGet = {
                "http://hc.apache.org/",
                "http://hc.apache.org/httpcomponents-core/",
                "http://hc.apache.org/httpcomponents-client/",
                "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[i]);
            threads[i] = 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();
        }

        // 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);
            }
        }

    }

}