Sending 2 objects through sockets?

Hi there,
I have 2 questoins here...
The first is....
Ive made a simple game that moves a image around a screen using the arrow keys. When i start the server it listens for connections and then I run the client. I'm able to get 2 instances of the objects running in 2 different swing frames but at the moment when I move the image around the screen it only moves in one window and not in the other. I would like the coordinates of the image in one window to be the same as the other when I move it.
this is my server class...
public void run() {
           try {
              oos.writeObject(pgf.getPacmanGamePanel().getPacmanGame());
              oos.writeObject(pgf.getPacmanGamePanel().getGhost());i move the pacmanGame on my PacmanGamePanel(pgp) which is on a pacmanGameFrame(pgf)
This is my Client class....
public static void main(String argv[]) {
            PacmanGameFrame pgf = new PacmanGameFrame();
           ObjectOutputStream oos = null;
           ObjectInputStream ois = null;
           //ObjectInputStream ois2 = null;
           Socket socket = null;
           PacmanGame pacgame = null;
           Ghost ghost = null;
           int port = 4444;
           try {
             // open a socket connection
             socket = new Socket("localhost", port);
             // open I/O streams for objects
             oos = new ObjectOutputStream(socket.getOutputStream());
             ois = new ObjectInputStream(socket.getInputStream());
             //ois2 = new ObjectInputStream(socket.getInputStream());
             while (true) {
                    // read an object from the server
                    pacgame = (PacmanGame) ois.readObject();
                    ghost = (Ghost) ois.readObject();
                    oos.reset();
                    I was hoping you could tell me why its not sending the object over from my client.
The second thing is i've coded a Ghost class the exact same way as my PacmanGame class which contains how the image moves around the screen and its methods etc. For some reason its not displaying at all on either the client or the server when i try to send the object across.
I am trying the same way as sending the pacmanGame() but it doesn't work....
public void run() {
           try {
              oos.writeObject(pgf.getPacmanGamePanel().getPacmanGame());
              oos.writeObject(pgf.getPacmanGamePanel().getGhost());I have a panel class which prints out the coordinates of the ghost
public void paint(Graphics g) {
        super.paint(g);
        if(ingame) {
             Graphics2D g2d = (Graphics2D)g;
            g2d.drawImage(pacmanGame.getImage(), pacmanGame.getX(), pacmanGame.getY(), this);
        for (int i = 0; i < ghosts.size(); i++) {
             Ghost ghost = (Ghost)ghosts.get(i);
             if(ghost.isVisible())
                  g2d.drawImage(ghost.getImage(), ghost.getX(), ghost.getY(), this);
        g2d.setColor(Color.WHITE);
        else {
             System.out.println("GAME OVER");
        Toolkit.getDefaultToolkit().sync();
        g.dispose();
    }Help on either question would be great.
1. why wont the image move on both server and client sides.
2. How can i get my ghost class to display?
If you need more info/code let me know..
Thanks alot.

Ok i called flush() on the output and commented out reset() on the input but still the same problem.
oos.writeObject(pgf.getPacmanGamePanel().getPacmanGame());
              oos.writeObject(pgf.getPacmanGamePanel().getGhost());
              oos.flush();
pacgame = (PacmanGame) ois.readObject();
                    ghost = (Ghost) ois.readObject();I think i've figured it out now and its to do with my paint() within gamePanel..
public class PacmanGamePanel extends JPanel implements ActionListener {
    private Timer timer;
    private PacmanGame pacmanGame;
    private Ghost ghost;
    private ArrayList ghosts;
    private boolean ingame;
    private int B_WIDTH;
    private int B_HEIGHT;
    private int[][] pos = {
              {50, 50}
public void paint(Graphics g) {
        super.paint(g);
        if(ingame) {
             Graphics2D g2d = (Graphics2D)g;
            g2d.drawImage(pacmanGame.getImage(), pacmanGame.getX(), pacmanGame.getY(), this);
        for (int i = 0; i < ghosts.size(); i++) {
             Ghost ghost = (Ghost)ghosts.get(i);
             if(ghost.isVisible())
                  g2d.drawImage(ghost.getImage(), ghost.getX(), ghost.getY(), this);
        g2d.setColor(Color.WHITE);
        else {
             System.out.println("GAME OVER");
        Toolkit.getDefaultToolkit().sync();
        g.dispose();
    }Can you help?

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        System.out.println("Accepted a connection from: " + bSocket.getInetAddress());
        brokerServer(bSocket);
        bSocket.close();
        System.out.println("Connection closed");
      catch (Exception e) { e.printStackTrace(); }
Broker Server
public void brokerServer(Socket bSocket) {
    BufferedReader in = null;
    ObjectOutputStream oos = null;
    PrintWriter out = null;
    ObjectInputStream ois = null;
    try {
      while (true) {
        oos = new ObjectOutputStream(new DataOutputStream(bSocket.getOutputStream()));
        out = new PrintWriter(new OutputStreamWriter(bSocket.getOutputStream()));
        ois = new ObjectInputStream(bSocket.getInputStream());
        in = new BufferedReader(new InputStreamReader(bSocket.getInputStream()));
        out.println("Connection with Broker on port " + brokerID + " established");
        out.flush();
        //read in first line
        String str = in.readLine();
        //if lineis null, break while loop
        if (str == null) break;
        else {
          //a request is recieved from user to get user certificate
          if (str.trim().equals("GETUSERCERT")) {
            //read in the userName, size of paywords and user publick key (used in certificate)
            String userName = in.readLine();
            String size = in.readLine();
            PublicKey userPk = (PublicKey) ois.readObject();
            //generate user certificate
            UserCertificate uc = generateUserCertificate(userName, userPk, Integer.parseInt(size, 10));
            //send text to user stating next message is user certififcate
            out.println("SENDUSERCERT");
            out.flush();
            //user Certificate
            oos.writeObject( (UserCertificate) uc);
            oos.flush();
            break;
          if (str.trim().equals("FINISH"))
            break;
        ois.close();
        oos.close();
        out.close();
        in.close();
    catch(Exception e) { e.printStackTrace(); }
This is the client
private void requestUserCertificate(int sizeOfPaywordChain, String BrokerID) {
    String host = "localhost";
    ObjectOutputStream oos = null;
    ObjectInputStream ois = null;
    PrintWriter out = null;
    BufferedReader in = null;
    Socket u2bSocket = null;
    try {
      u2bSocket = new Socket(host, Integer.parseInt(BrokerID));
      System.out.println("Connecting to Broker on port " + BrokerID);
      ois = new ObjectInputStream(new DataInputStream(u2bSocket.getInputStream()));
      oos = new ObjectOutputStream(u2bSocket.getOutputStream());
      out = new PrintWriter(new OutputStreamWriter(u2bSocket.getOutputStream()));
      in = new BufferedReader(new InputStreamReader(u2bSocket.getInputStream()));
      //Informs broker that a user certificate is being requested
      out.println("GETUSERCERT");
      //send to broker, username and size of payword chain
      out.println(userName);
      out.println(sizeOfPaywordChain);
      out.flush();
      //send user's public key accross
      oos.writeObject((PublicKey) userPublicKey);
      oos.flush();
      out.println("FINISH");
      out.flush();
      //wait for response
      while(true) {
        //read in line
        String str = in.readLine();
        //if line is null, break while loop
        if (str == null) break;
        //if line read is "SENDUSERCERT" then next line is userCertificate sent from Broker
        if (str.trim().equals("SENDUSERCERT")) {
          //read User Certificate
          userCert = (UserCertificate)ois.readObject();
          break;
        else System.out.println(str);
      //close connections and streams
      u2bSocket.close();
      ois.close();
      oos.close();
      out.close();
      in.close();
    catch (Exception e) { e.printStackTrace(); }
}I will be regurarly checking this thread, so any other code which you think i should post i will, i can post is ASAP.
The problem
First time i run the programs, it works perfectly, however when i run the client program again, it shows this error
java.io.EOFException
     at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2438)
     at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1245)
     at java.io.ObjectInputStream.readObject(ObjectInputStream.java:324)
     at User.requestUserCertificate(User.java:75)
     at User.main(User.java:278)the broker server doesn't display anything.
Would anyone have any idea whats going on??
Sometimes when i run it, it might display the above error, or it might work. its about 50/50. I have read heaps of similar problems people have had and posted on this forum, but i still don't have any luck in solving this delema.
Any kind of help will be greatly appreciated.
Rish

I see one problem with the code. You are opening both ObjectInputStream ois and a BufferedReader in on the same socket. This won't work as "in" will read ahead to fill up its buffer. This could cause "ois" to find the socket already at end of stream prematurely. I would only use the Object Streams and send the strings as objects.

Send many files through a socket without closing Buffered Streams?

Hi,
I have an application that sends/receives files through a socket. To do this, on the receiver side I have a BufferedInputStream from the socket, and a BufferedOutputStream to the file on disk.
On the sender side I have the same thing in reverse.
As you know I can't close any stream, ever.. because that closes the underlying socket (this seems stupid..?)
therefore, how can I tell the receiver that it has reached the end of a file?
Can you show me any examples that send/receive more than one file without closing any streams/sockets?

Hi,
As you know I can't close any stream, ever.. because that closes the underlying socket (this seems stupid..?)Its not if you want to continuosly listen to the particular port.. like those of server, you need to use ServerSocket.
for sending multiple files the sender(Socket) can request the file to server (ServerSocket). read the contents(file name) and then return the file over same connection, then close the connection.
For next file you need to request again, put it in loop that will be better.
A quick Google gives me this.
Regards,
Santosh.

Sending 2 objects through sockets?

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