NullPointerException all of a sudden...

Question

This used to work just fine, but today, for some reason it doesn't. Everything seems to work since nothing lights up in red or anything in Eclipse. If I write "outputGUI." Eclipse finds the textArea so everything seems to be "connected". Does anyone know why this doesn't work?
final class ServerListener extends Thread{
     private BufferedReader fromServer;
     private ServerGUI outputGUI;
     public ServerListener(BufferedReader fromServer, ServerGUI allClientsGUI) throws IOException{
          this.fromServer = fromServer;
          outputGUI=allClientsGUI;
     public void run(){
          String lineFromServer;
          try{
               while((lineFromServer = fromServer.readLine()) !=null){
                    outputGUI.textArea.append("From Servern: " + lineFromServer + "\n");   //THIS GIVES ME NULLPOINTEREXCEPTION
                    System.out.println(lineFromServer);   //THIS WORKS
          catch(IOException e){
}

Answer 1

outputGUI.textArea.append("From Servern: " + lineFromServer + "\n");So either outpugGUI or outputGUI.textArea is null. Find out which.
catch(IOException e){
}You should not ignore exceptions. At a minimum, you should print out the exception and the stack trace.