Java example source code file (ADatagramSocket.java)

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Java - Java tags/keywords

adatagramsocket, datagrampacket, datagramsocket, datagramsocketimplfactory, inetaddress, ioexception, net, network, quoteserverthread, runtimeexception, setting, string, util

The ADatagramSocket.java Java example source code

/*
 * Copyright (c) 1999, 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 4132931
 * @summary DatagramSocket should use a factory for its impl
 *
 * @build ADatagramSocket
 * @run shell ADatagramSocket.sh
 */
import java.io.*;
import java.net.*;
import java.util.*;

public class ADatagramSocket {
    public static void main(String[] args) throws IOException {
        // testing out setDatagramSocketImplFactory
        System.err.println("setting DatagramSocketImplFactory...");
        try {
          DatagramSocket.setDatagramSocketImplFactory(new java.net.MyDatagramSocketImplFactory());
        } catch (Exception ex) {
          throw new RuntimeException("Setting DatagramSocketImplFactory failed!");
        }
        new QuoteServerThread().start();

        // get a datagram socket
        DatagramSocket socket = new DatagramSocket();

        // send request
        byte[] buf = new byte[256];
        InetAddress address = InetAddress.getLocalHost();
        DatagramPacket packet = new DatagramPacket(buf, buf.length, address, 4445);
        socket.send(packet);

        // get response
        packet = new DatagramPacket(buf, buf.length);
        socket.receive(packet);

        // display response
        String received = new String(packet.getData(), 0);
        System.err.println("Success!! Server current time is: " + received);

        socket.close();
    }
}

class QuoteServerThread extends Thread {

    protected DatagramSocket socket = null;

    public QuoteServerThread() throws IOException {
        this("QuoteServerThread");
    }

    public QuoteServerThread(String name) throws IOException {
        super(name);
        socket = new DatagramSocket(4445);
    }

    public void run() {
      try {
        byte[] buf = new byte[256];

        // receive request
        DatagramPacket packet = new DatagramPacket(buf, buf.length);
        socket.receive(packet);

        // figure out response
        String dString = null;
        dString = new Date().toString();
        buf = dString.getBytes();

        // send the response to the client at "address" and "port"
        InetAddress address = packet.getAddress();
        int port = packet.getPort();
        packet = new DatagramPacket(buf, buf.length, address, port);
        socket.send(packet);
      } catch (IOException e) {
        e.printStackTrace();
      }
      socket.close();
    }
}