Server/Client Socket Connection

Question

Hi, I am trying to program a simple server/client socket connection program, the main function is to send and receive objects between them. I somehow went wrong and the connection between them keeps terminating right after establishing connection. Is there anything I can do to resolve this?
This is gonnna be kinda long post.. sorry. These are the code that starts and ends the socket connection. I'm kinda desperate for this to work.. so thanks in advance.
appinterface.java:
//Set up server to receive communications; process connections. 1x.
     public void runServer () {
          try {
               //Create a ServerSocket
               server = new ServerSocket(12345, 100);
               try {
                         waitForSockConnection();     //Wait for a connection.
                         getSockStreams();               //Get input & output streams.
                         establishDbConnection();     //Open up connection to DB.
               finally {
                         closeSockConnection(); //Close connection.
          //Process problems with I/O
          catch(IOException ioException) {
               displayMessage("I/O Error: " + ioException);
               runServer();
     //Wait for connection to arrive, then display connection info
     private void waitForSockConnection() throws IOException {
          displayMessage("Waiting for connection");
          connection = server.accept(); //Allow server to accept connection.
          displayMessage("Connection received from: " + connection.getInetAddress().getHostName());
     //Get streams to send and receive data.
     private void getSockStreams() throws IOException {
          //Set up output streams for objects
          ObjectOutputStream output = new ObjectOutputStream(connection.getOutputStream());
          output.flush(); //Flush output buffer to send header information.
          //Set up input stream for objects.
          ObjectInputStream input = new ObjectInputStream(connection.getInputStream());
          try {
          classHolderServer holderObj = new classHolderServer();
          holderObj = (classHolderServer)input.readObject();
          processSockConnection(holderObj);
          displayMessage("Got I/O Streams");
          //Catch problems reading from client
          catch (ClassNotFoundException classNotFoundException) {
                         displayMessage("Unknown object type received");
     //Process connection with client.
     private void processSockConnection(classHolderServer holderObj) throws IOException {
          //sendMessage("Connection Successful");
                    //True is query, and false is auth.
                    if(holderObj.type1==true)
                         processDbStatement(holderObj.type2, holderObj.sqlquery);
                    else {
                         authCheck(holderObj.userName, holderObj.passWord);
                         if(!authCheck)
                         closeDbConnection();
     //Send messages to client.
     private void sendMessage(String message) {
          // Send message to client
          try {
               ObjectOutputStream output = new ObjectOutputStream(connection.getOutputStream());
               output.flush();
               output.writeObject(message);
               output.flush();
               displayMessage("Message Sent:" + message);
          catch (IOException ioException) {
               displayMessage("\nError Sending Message: " + message);
     //Send object to client
     private void sendObject(Object holderObj) {
               // Send object to client
               try {
                    ObjectOutputStream output = new ObjectOutputStream(connection.getOutputStream());
                    output.writeObject(holderObj);
                    output.flush();
                    displayMessage("\nObject sent");
               //Process problems sending object
               catch (IOException ioException) {
                    displayMessage("\nError writing object");
     //Close streams and socket.
     private void closeSockConnection() {
               displayMessage("Terminating connection");
               try {
                    //output.close();
                    //input.close();
                    connection.close();
                    closeDbConnection();
                    this.userName = null;
                    this.passWord = null;
                    this.receiverId = 0;
                    this.authCheck = false;
               catch (IOException ioException) {
                    displayMessage("I/O Error: " + ioException);
          }Client:
private void runClient() {
          //Connect to sever and process messages from server.
          try{
               connectToServer();
               getStreams();
               processConnection();
          //Server closed connection.
          catch(EOFException eofException) {
               //displayMessage"Client Terminated Connection");
          //Process problems communicating with server.
          catch (IOException ioException) {
               //displayMessage"Communication Problem");
          finally {
               closeConnection();
     //Connect to server
     private void connectToServer() throws IOException {
          //displayMessage("Attempting connection\n");
          //Create Socket to make connection to sever.
          client = new Socket(InetAddress.getByName(chatServer), 12345);
          //Display connection information
          //displayMessage("Connected to: " + client.getInetAddress().getHostName());
     //Get streams to send and receive data.
     private void getStreams() throws IOException {
          //Set up output stream for objects.
          ObjectOutputStream output = new ObjectOutputStream(client.getOutputStream());
          output.flush(); //Flush outout buffer to send header information.
          //Set up input stream for objects.
          ObjectInputStream input = new ObjectInputStream(client.getInputStream());
          //displayMessage("\nGot I/O streams\n");
     //Close socket connection.
     private void closeConnection() {
          //displayMessage("\nClosing connection");
          try {
               ObjectOutputStream output = new ObjectOutputStream(client.getOutputStream());
               output.close();
               ObjectInputStream input = new ObjectInputStream(client.getInputStream());
               input.close();
               client.close();
               authCheck=false;
          catch(IOException ioException) {
               ioException.printStackTrace();
     //Send data to server.
     private void sendObject(classHolderClient queryObj) {
          try {
               output.writeObject(queryObj);
               output.flush();
               //displayMessage("Please wait..");
          //Process problems sending object.
          catch (IOException ioException) {
               //displayMessage("\nError writing object");
     //Process connection with server.
     private void processConnection() throws IOException {
          try{
               classHolderClient holderObj = new classHolderClient();
               holderObj = (classHolderClient)input.readObject();
               if(holderObj.type2==2) {
                         this.authCheck=holderObj.authCheck;
                         this.userName=holderObj.userName;
                         this.passWord=holderObj.passWord;
          catch(ClassNotFoundException classNotFoundException) {
               //displayMessage(classNotFoundException);
          }

Answer 1

private ObjectOutputStream output = new ObjectOutputStream(client.getOutputStream());Like this? But this will cause an error asking me to catch an exception:
C:\Documents and Settings\Moon\My Documents\Navi Projects\School\OOPJ Project\Prototype\GPS-Lite v2 Alpha Debugger\client.java:41: unreported exception java.io.IOException; must be caught or declared to be thrown
        private ObjectOutputStream output = new ObjectOutputStream(client.getOutputStream());
                                                                                         ^
C:\Documents and Settings\Moon\My Documents\Navi Projects\School\OOPJ Project\Prototype\GPS-Lite v2 Alpha Debugger\client.java:41: unreported exception java.io.IOException; must be caught or declared to be thrown
        private ObjectOutputStream output = new ObjectOutputStream(client.getOutputStream());
                                            ^
2 errors