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Line 21... Line 21...
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public class P2_Server
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public class P2_Server
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{
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{
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    private static int portNumber = 1337;
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    private static int portNumber = 1337;
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    private static int dropEvery = -1;
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    private static int dropEvery = -1;
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    private static int sendCount = 0;
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    private static boolean dropPacket = false;
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    private static DatagramPacket packet;
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    private static DatagramPacket packet;
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    private static DatagramSocket socket;
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    private static DatagramSocket socket;
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    /**
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    /**
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     * Method: readPacket()
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     * Method: readPacket()
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     * Purpose: write a message to the last client that sent us a message,
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     * Purpose: write a message to the last client that sent us a message,
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     * while dropping every n-th message, as specified by the client.
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     * while dropping every n-th message, as specified by the client.
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     */
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     */
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    public static boolean writePacket (byte type, byte[] data)
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    public static boolean writePacket (byte type, byte[] data)
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    {
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    {
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        if (sendCount >= dropEvery && type != P2_Packet.QUIT)
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        {
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            System.out.println ("Dropped a packet");
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            sendCount = 0; // reset the sendCount
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            return true;   // Fake send
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        }
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        else { sendCount++; }
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        InetAddress address = packet.getAddress();
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        InetAddress address = packet.getAddress();
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        int port = packet.getPort();
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        int port = packet.getPort();
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        byte[] buf = P2_Packet.createPacket (type, data);
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        byte[] buf = P2_Packet.createPacket (type, data);
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        packet = new DatagramPacket (buf, buf.length, address, port);
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        packet = new DatagramPacket (buf, buf.length, address, port);
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     * Purpose: Open a listening UDP socket, and convert a client's
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     * Purpose: Open a listening UDP socket, and convert a client's
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     * requests from 4B encoding to 5B encoding.
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     * requests from 4B encoding to 5B encoding.
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     */
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     */
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    public static void main (String[] args) throws Exception
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    public static void main (String[] args) throws Exception
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    {
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    {
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        boolean done = false;
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        boolean done = false, droppedLast = false;
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        socket = new DatagramSocket(portNumber);
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        socket = new DatagramSocket(portNumber);
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        packet = null;
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        packet = null;
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        String s;
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        String s;
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        P2_Packet decodedPacket = null;
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        P2_Packet decodedPacket = null;
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        byte[] pData;
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        byte[] pData;
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        done = false;
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        done = false;
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        // Keep reading until we get a quit packet
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        // Keep reading until we get a quit packet
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        while (!done)
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        while (!done)
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        {
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        {
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            decodedPacket = readPacket ();
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            decodedPacket = readPacket ();
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            // Check and see if we got a quit message
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            if (decodedPacket.getPacketType() == P2_Packet.QUIT)
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            if ((decodedPacket.getPacketNumber() == dropEvery) && !droppedLast)
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            {
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            {
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                done = true;
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                droppedLast = true;
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                writePacket(P2_Packet.QUIT);
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                continue;
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                continue;
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            }
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            }
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            if (decodedPacket.getPacketType() == P2_Packet.TRANSREQ)
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            {
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                try {
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            droppedLast = false;
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                    pData = P2_EncDec.convert4B (decodedPacket.getPacketData());
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            switch (decodedPacket.getPacketType())
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            {
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                case P2_Packet.TRANSREQ:
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                    try {
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                        pData = P2_EncDec.convert4B (decodedPacket.getPacketData());
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                    writePacket (P2_Packet.TRANSREPL, pData);
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                        writePacket (P2_Packet.TRANSREPL, pData);
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                } catch (IllegalArgumentException e) {
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                    } catch (IllegalArgumentException e) {
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                    System.out.println ("Recieved a bad packet");
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                        System.err.println ("Received a bad packet");
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                        writePacket (P2_Packet.BADPACKET);
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                    }
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                    break;
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                case P2_Packet.QUIT:
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                    writePacket (P2_Packet.QUIT);
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                    done = true;
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                    break;
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                default:
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                    System.err.println ("Got a packetType that I was not "
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                                      + "expecting here.");
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                    writePacket (P2_Packet.BADPACKET);
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                    writePacket (P2_Packet.BADPACKET);
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                    continue;
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                    break;
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                }
 - 
 
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            }
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            }
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 - 
 
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            System.out.println ("Got a strange packet type for this area");
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        }
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        }
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        // Close the socket
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        // Close the socket
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        socket.close();
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        socket.close();
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    }
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    }