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Java example source code file (B5045306.java)

This example Java source code file (B5045306.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

content\-length, exception, failed, httpcallback, ioexception, keep\-alive\-socketcleaner, management, net, network, response_data_length, runtimeexception, simplehttptransaction, string, testhttpserver, url

The B5045306.java Java example source code

/*
 * Copyright (c) 2005, 2012, 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 5045306 6356004 6993490
 * @library ../../httptest/
 * @build HttpCallback TestHttpServer HttpTransaction
 * @run main/othervm B5045306
 * @summary Http keep-alive implementation is not efficient
 */

import java.net.*;
import java.io.*;
import java.lang.management.*;

/* Part 1:
 * The http client makes a connection to a URL whos content contains a lot of
 * data, more than can fit in the socket buffer. The client only reads
 * 1 byte of the data from the InputStream leaving behind more data than can
 * fit in the socket buffer. The client then makes a second call to the http
 * server. If the connection port used by the client is the same as for the
 * first call then that means that the connection is being reused.
 *
 * Part 2:
 * Test buggy webserver that sends less data than it specifies in its
 * Content-length header.
 */

public class B5045306
{
    static SimpleHttpTransaction httpTrans;
    static TestHttpServer server;

    public static void main(String[] args) throws Exception {
        startHttpServer();
        clientHttpCalls();
    }

    public static void startHttpServer() {
        try {
            httpTrans = new SimpleHttpTransaction();
            server = new TestHttpServer(httpTrans, 1, 10, 0);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void clientHttpCalls() {
        try {
            System.out.println("http server listen on: " + server.getLocalPort());
            String baseURLStr = "http://" + InetAddress.getLocalHost().getHostAddress() + ":" +
                                  server.getLocalPort() + "/";

            URL bigDataURL = new URL (baseURLStr + "firstCall");
            URL smallDataURL = new URL (baseURLStr + "secondCall");

            HttpURLConnection uc = (HttpURLConnection)bigDataURL.openConnection();

            //Only read 1 byte of response data and close the stream
            InputStream is = uc.getInputStream();
            byte[] ba = new byte[1];
            is.read(ba);
            is.close();

            // Allow the KeepAliveStreamCleaner thread to read the data left behind and cache the connection.
            try { Thread.sleep(2000); } catch (Exception e) {}

            uc = (HttpURLConnection)smallDataURL.openConnection();
            uc.getResponseCode();

            if (SimpleHttpTransaction.failed)
                throw new RuntimeException("Failed: Initial Keep Alive Connection is not being reused");

            // Part 2
            URL part2Url = new URL (baseURLStr + "part2");
            uc = (HttpURLConnection)part2Url.openConnection();
            is = uc.getInputStream();
            is.close();

            // Allow the KeepAliveStreamCleaner thread to try and read the data left behind and cache the connection.
            try { Thread.sleep(2000); } catch (Exception e) {}

            ThreadMXBean threadMXBean = ManagementFactory.getThreadMXBean();
            if (threadMXBean.isThreadCpuTimeSupported()) {
                long[] threads = threadMXBean.getAllThreadIds();
                ThreadInfo[] threadInfo = threadMXBean.getThreadInfo(threads);
                for (int i=0; i<threadInfo.length; i++) {
                    if (threadInfo[i].getThreadName().equals("Keep-Alive-SocketCleaner"))  {
                        System.out.println("Found Keep-Alive-SocketCleaner thread");
                        long threadID = threadInfo[i].getThreadId();
                        long before = threadMXBean.getThreadCpuTime(threadID);
                        try { Thread.sleep(2000); } catch (Exception e) {}
                        long after = threadMXBean.getThreadCpuTime(threadID);

                        if (before ==-1 || after == -1)
                            break;  // thread has died, OK

                        // if Keep-Alive-SocketCleaner consumes more than 50% of cpu then we
                        // can assume a recursive loop.
                        long total = after - before;
                        if (total >= 1000000000)  // 1 second, or 1 billion nanoseconds
                            throw new RuntimeException("Failed: possible recursive loop in Keep-Alive-SocketCleaner");
                    }
                }
            }

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            server.terminate();
        }
    }
}

class SimpleHttpTransaction implements HttpCallback
{
    static boolean failed = false;

    // Need to have enough data here that is too large for the socket buffer to hold.
    // Also http.KeepAlive.remainingData must be greater than this value, default is 256K.
    static final int RESPONSE_DATA_LENGTH = 128 * 1024;

    int port1;

    public void request(HttpTransaction trans) {
        try {
            String path = trans.getRequestURI().getPath();
            if (path.equals("/firstCall")) {
                port1 = trans.channel().socket().getPort();
                System.out.println("First connection on client port = " + port1);

                byte[] responseBody = new byte[RESPONSE_DATA_LENGTH];
                for (int i=0; i<responseBody.length; i++)
                    responseBody[i] = 0x41;
                trans.setResponseEntityBody (responseBody, responseBody.length);
                trans.sendResponse(200, "OK");
            } else if (path.equals("/secondCall")) {
                int port2 = trans.channel().socket().getPort();
                System.out.println("Second connection on client port = " + port2);

                if (port1 != port2)
                    failed = true;

                trans.setResponseHeader ("Content-length", Integer.toString(0));

                 /* Force the server to not respond for more that the timeout
                  * set by the keepalive cleaner (5000 millis). This ensures the
                  * timeout is correctly resets the default read timeout,
                  * infinity. See 6993490. */
                System.out.println("server sleeping...");
                try {Thread.sleep(6000); } catch (InterruptedException e) {}

                trans.sendResponse(200, "OK");
            } else if(path.equals("/part2")) {
                System.out.println("Call to /part2");
                byte[] responseBody = new byte[RESPONSE_DATA_LENGTH];
                for (int i=0; i<responseBody.length; i++)
                    responseBody[i] = 0x41;
                trans.setResponseEntityBody (responseBody, responseBody.length);

                // override the Content-length header to be greater than the actual response body
                trans.setResponseHeader("Content-length", Integer.toString(responseBody.length+1));
                trans.sendResponse(200, "OK");

                // now close the socket
                trans.channel().socket().close();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

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