Java example source code file (B6518816.java)

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Java - Java tags/keywords

b6518816, executorservice, headers, httphandler, inetsocketaddress, inputstream, interruptedexception, ioexception, myhandler, net, network, outputstream, part, runtimeexception, ten_mb, threading, threads, url, util

The B6518816.java Java example source code

/*
 * Copyright (c) 2007, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

/*
 * @test
 * @bug 6518816
 * @run main/othervm B6518816
 */

import java.net.*;
import java.util.*;
import java.io.*;
import com.sun.net.httpserver.*;
import java.util.concurrent.Executors;
import java.util.concurrent.ExecutorService;

public class B6518816
{
    com.sun.net.httpserver.HttpServer httpServer;
    ExecutorService executorService;

    public static void main(String[] args)
    {
        new B6518816();
    }

    public B6518816()
    {
        try {
            startHttpServer();
            doClient();
        } catch (IOException ioe) {
            System.err.println(ioe);
        }
    }

    final static int MAX_CONNS = 10;
    final static int TEN_MB = 10 * 1024 * 1024;
    static boolean stopped = false;

    /*
     * we send approx 100MB and if more than 90MB is retained
     * then the bug is still there
     */
    void doClient() {

        try {
            InetSocketAddress address = httpServer.getAddress();
            List<HttpURLConnection> conns = new LinkedList();

            long totalmem1=0, totalmem2=0;
            System.gc();
            Runtime runtime = Runtime.getRuntime();
            totalmem1 = runtime.totalMemory() - runtime.freeMemory();
            System.out.println ("Sending " + (TEN_MB*MAX_CONNS/1024) + " KB");
            System.out.println ("At start: " + totalmem1/1024 + " KB");

            byte [] buf = new byte [TEN_MB];

            for (int j=0; j<MAX_CONNS; j++) {

                URL url = new URL("http://localhost:"+address.getPort()+"/test/");
                HttpURLConnection uc = (HttpURLConnection)url.openConnection();
                uc.setDoOutput (true);
                OutputStream os = uc.getOutputStream ();
                os.write (buf);
                InputStream is = uc.getInputStream();
                int resp = uc.getResponseCode();
                if (resp != 200) {
                    throw new RuntimeException("Failed: Part 1, Response code is not 200");
                }
                while  (is.read() != -1) ;
                is.close();

                conns.add (uc);
            }
            httpServer.stop(1);
            httpServer = null;
            executorService.shutdown();
            executorService = null;
            stopped = true;
            buf = null;
            System.runFinalization();
            try {Thread.sleep (1000); } catch (InterruptedException e){}
            System.gc();
            try {Thread.sleep (1000); } catch (InterruptedException e){}
            System.gc();
            totalmem2 = runtime.totalMemory() - runtime.freeMemory();
            System.out.println ("At end: " + totalmem2/1024 + " KB");
            long diff = (totalmem2 - totalmem1) ;;
            System.out.println ("Diff " + diff/1024 + " kbytes ");
            if (diff > (TEN_MB*MAX_CONNS*0.9)) {
                /* if >= 90 MB retained, then problem still there */
                throw new RuntimeException ("Excessive memory retained");
            }

        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException ("IOException");
        } finally {
            if (!stopped) {
                httpServer.stop(1);
                executorService.shutdown();
            }
        }
    }

    /**
     * Http Server
     */
    public void startHttpServer() throws IOException {
        httpServer = com.sun.net.httpserver.HttpServer.create(new InetSocketAddress(0), 0);

        // create HttpServer context for Part 1.
        HttpContext ctx = httpServer.createContext("/test/", new MyHandler());

        executorService = Executors.newCachedThreadPool();
        httpServer.setExecutor(executorService);
        httpServer.start();
    }

    class MyHandler implements HttpHandler {
        public void handle(HttpExchange t) throws IOException {
            InputStream is = t.getRequestBody();
            Headers reqHeaders = t.getRequestHeaders();
            Headers resHeaders = t.getResponseHeaders();
            byte[] buf = new byte [16 * 1024];
            while (is.read (buf) != -1) ;
            t.sendResponseHeaders(200, -1);
            t.close();
        }
    }

}