GUi's

Question

Hey I have a program that runs a server and database check every second or two to make sure that they are still alive,the problem that I am having is that the checks are carried out by an external class and when an error occurs I want the program to stop the user from doing anything and move them to another gui the problem is how can I fins out which GUI of class file was open when the eror occured so that I can close it.
Thanks

Answer 1

Thanks for replying stevejluke, the problem is that
when an error is picked up by the server it display a
new gui and leaves the old one open. What I wanted to
do is get the new window to close the old one if it is
possible.Can you post a simple example of what you are doing that is not working? For instance, at the bottom of this page is an example of some simple code that does work... Could you change it so that it works sorta like yours does, ie, the KeyboardFocusManager doesn't work? Then post the parts of the code you changed back here and I will check the difference and see why yours might not be working...
If you can't seem to get it to behave the same, a better explanation will be needed. Like are you preforming a long operation in the Event Dispatch Thread? Are there multiple windows open and the wrong one is being closed?
and when you post the code, don't forget to use [code] tags (see Formatting Help for more)
import javax.swing.*;
import java.awt.Component;
import java.awt.LayoutManager;
* UltraSimpleGUI
* Just a Button to Push.  Uses JButtonAction class (see below)
* as the ActionListener.  The Runnable required is created in
* the main method.
public class UltraSimpleGUI extends JFrame
     public UltraSimpleGUI(Runnable[] actions)
          super ("Press The Button");
          JButton jb = new JButton ("Press Me");
          jb.addActionListener(new JButtonAction(actions[0]));
          getContentPane().add(jb);
          setSize(300,300);
          setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          setVisible(true);
     public static void main(String[] args)
          /* Runnable for the button(s) for their actionListener.  This
           * one just creates an IndexOutOfBoundsException.
          Runnable procWithException = new Runnable()
               public void run()
                    try
                         int[] array = new int[4];
                         array[19] = 387;
                    } catch (IndexOutOfBoundsException ioobe)
                         // Fatal error.  End program when it occurs
                         new ErrorCaptureDialog(ioobe, true);
                    } catch (Exception ex)
                         //Non-fatal error.  Log and inform, but don't die
                         new ErrorCaptureDialog(ex, false);
          new UltraSimpleGUI(new Runnable[]{procWithException});
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
* JButtonAction
* ActionListener that takes a Runnable to determine what
* it should do...  Maybe I should rename this better...
public class JButtonAction implements ActionListener
     private Runnable toDo;
     public JButtonAction(Runnable action)
          toDo = action;
     public void actionPerformed(ActionEvent ae)
          toDo.run();
import javax.swing.*;
import java.awt.BorderLayout;
* ErrorCaptureDialog
* Display an Error Message in a Dialog.
* Kill the currently focused Window.  Send the error
* stack trace to System.err, and Optionally, end the
* Program.
* @author Owner
public class ErrorCaptureDialog extends JDialog implements Runnable
     private boolean fatal = false;
     private java.awt.Window currentlyFocusedWindow;
     private static final JLabel standardMessage =
                    new JLabel("See Error Log for Details");
     public ErrorCaptureDialog(Exception ex, boolean end)
          super(new java.awt.Frame(), ex.getClass().getName());
          fatal = end;
          currentlyFocusedWindow = java.awt.KeyboardFocusManager
                              .getCurrentKeyboardFocusManager()
                              .getActiveWindow();
          if (fatal)  currentlyFocusedWindow.dispose();
          JTextArea errorMessage = JTextArea(ex.getClass().getName()+": "+ex.getMessage());
               errorMessage.setEditable(false);
               errorMessage.setBorder(null);
               errorMessage.setOpaque(false);
               errorMessage.setLineWrap(true);
               errorMessage.setWrapStyleWord(true);
               errorMessage.setFont(standardMessage.getFont());
          JScrollPane errScroller = new JScrollPane(errorMessage);
               errScroller.setPreferredSize(new java.awt.Dimension (400, 40));
          JButton jb = new JButton("Ok");
               jb.addActionListener(new JButtonAction(this));
          JPanel errPanel = new JPanel();
               errPanel.setLayout(new BorderLayout());
               errPanel.add(errScroller);
               errPanel.add(standardMessage, BorderLayout.SOUTH);
          JPanel butnPanel = new JPanel();
               butnPanel.add(jb);
          JPanel content = new JPanel();
               content.setLayout(new BorderLayout());
               content.add(errPanel, BorderLayout.CENTER);
               content.add(butnPanel, BorderLayout.SOUTH);
          setContentPane(content);
          pack();
          setVisible(true);
          System.err.println();
          System.err.println(new java.util.Date().toString());
          ex.printStackTrace(System.err);
     public void run()
          this.dispose();
          if (fatal)
               System.exit(1);
}