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Problem with threads running javaw

Update:10-11Source: network consolidation
Having a problem with multi thread programming using client server sockets. The program works find when starting the the application in a console using java , but when using javaw the program doesnt die and have to kill it in the task manager. The program doesnt display any of my gui error messages either when the server disconnect the client. all works find in a console. any advice on this as I havent been able to understand why this is happening? any comment would be appreciated.

The Best Answer

Try and post a minimum code sample of your app which
does not work.
When using javaw, make sure you redirect the standard
error and standard output streams to file.
Graeme.Hi Graeme,
I dont understand what you mean by redirection to file? some of my code below.
The code works fine under a console, code is supposed to exit when the client (the other server )disconnects. the problem is that but the clientworker side of the code still works. which under console it doesnt.
public class Server{
ServerSocket aServerSocket;
Socket dianosticsSocket;
Socket nPortExpress;
ClientListener aClientListener;
LinkedList queue = new LinkedList();
int port = 0;
int clientPort = 0;
String clientName = null;
boolean serverAlive = true;
* Server constructor generates a server
* Socket and then starts a client threads.
* @param aPort      socket port of local machine.
public Server(int aPort, String aClientName, int aClientPort){
port = aPort;
clientName = aClientName;
clientPort = aClientPort;
// create a new thread
aServerSocket = new ServerSocket(port) ;
// connect to the nPortExpress
aClientListener = new ClientListener(InetAddress.getByName(clientName), clientPort, queue,this);
// aClientListener.setDaemon(true);
// start a dianostic port
DiagnosticsServer aDiagnosticsServer = new DiagnosticsServer(port,queue,aClientListener);
// System.out.println("Server is running on port " + port + "...");
// System.out.println("Connect to nPort");
catch(Exception e)
// System.out.println("ERROR: Server port " + port + " not available");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Server port " + port + " not available", JOptionPane.ERROR_MESSAGE);
serverAlive = false;
// connect the client
Socket aClient = aServerSocket.accept();
//System.out.println("open client connection");
//System.out.println("client local: "+ aClient.getLocalAddress().toString());
// System.out.println("client localport: "+ aClient.getLocalPort());
// System.out.println("client : "+ aClient.getInetAddress().toString());
// System.out.println("client port: "+ aClient.getLocalPort());
// make a new client thread
ClientWorker clientThread = new ClientWorker(aClient, queue, aClientListener, false);
// start thread
catch(Exception e)
//System.out.println("ERROR: Client connection failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client connection failure", JOptionPane.ERROR_MESSAGE);
}// end while
} // end constructor Server
void serverExit(){
     JOptionPane.showMessageDialog(null, "Server ","ERROR: nPort Failure", JOptionPane.ERROR_MESSAGE);
}// end class Server
*** connect to another server
public class ClientListener extends Thread{
InetAddress hostName;
int hostPort;
Socket hostSocket;
BufferedReader in;
PrintWriter out;
boolean loggedIn;
LinkedList queue;      // reference to Server queue
Server serverRef; // reference to main server
* ClientListener connects to the host server.
* @param aHostName is the name of the host eg server name or IP address.
* @param aHostPort is a port number of the host.
* @param aLoginName is the users login name.
public ClientListener(InetAddress aHostName, int aHostPort,LinkedList aQueue,Server aServer)      // reference to Server queue)
hostName = aHostName;
hostPort = aHostPort;
queue = aQueue;
serverRef = aServer;      
// connect to the server
hostSocket = new Socket(hostName, hostPort);
catch(IOException e){
//System.out.println("ERROR: Connection Host Failed");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort Failed", JOptionPane.ERROR_MESSAGE);     
} // end constructor ClientListener
** multi client connection server
ClientWorker(Socket aSocket,LinkedList aQueue, ClientListener aClientListener, boolean diagnostics){
queue = aQueue;
client = aSocket;
clientRef = aClientListener;
aDiagnostic = diagnostics;
} // end constructor ClientWorker
* run method is the main loop of the server program
* in change of handle new client connection as well
* as handle all messages and errors.
public void run(){
boolean alive = true;
String aSubString = "";
in = null;
out = null;
loginName = "";
loggedIn = false;
while (alive && client.isConnected()&& clientRef.hostSocket.isConnected()){
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(client.getOutputStream()));
out.println("WELCOME to diagnostics");
broadCastDia("Connect : diagnostics "+client.getInetAddress().toString());
else {       
out.println("WELCOME to Troy's Server");
broadCastDia("Connect : client "+client.getInetAddress().toString());
String line;
while(((line = in.readLine())!= null)){
StringTokenizer aStringToken = new StringTokenizer(line, " ");
clientRef.sendMessage(line); // send mesage out to netExpress
clientRef.sendMessage(line); // send mesage out to netExpress
} // end while
catch(Exception e){
// System.out.println("ERROR:Client Connection reset");
                         JOptionPane.showMessageDialog(null, (e.toString()),"ERROR:Client Connection reset", JOptionPane.ERROR_MESSAGE);     
broadCastDia("Disconnect : diagnostics "+client.getInetAddress().toString());
else {       
broadCastDia("Disconnect : client "+client.getInetAddress().toString());
// close the buffers and connection;
// System.out.println("out");
// remove from list
alive = false;
catch(Exception e){
// System.out.println("ERROR: Client Connection reset failure");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Client Connection reset failure", JOptionPane.ERROR_MESSAGE);     
}// end while
} // end method run
* method run - Generates io stream for communicating with the server and
* starts the client gui. Run also parses the input commands from the server.
public void run(){
boolean alive = true;
// begin to life the gui
// aGuiClient = new ClientGui(hostName.getHostName(), hostPort, loginName, this);
in = new BufferedReader(new InputStreamReader(hostSocket.getInputStream()));
out = new PrintWriter(new OutputStreamWriter(hostSocket.getOutputStream()));
while (alive && hostSocket.isConnected()){
String line;
while(((line = in.readLine())!= null)){
} // end while
} // end while
catch(Exception e){
//     System.out.println("ERRORa Connection to host reset");
JOptionPane.showMessageDialog(null, (e.toString()),"ERROR: Connection to nPort reset", JOptionPane.ERROR_MESSAGE);
     }catch(Exception a){
     JOptionPane.showMessageDialog(null, (a.toString()),"ERROR: Exception", JOptionPane.ERROR_MESSAGE);
alive = false;
} // end method run
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