I have a Swing runnable app which updates messages, then I have a Java servlet that gets messages from Paypal IPN (Instant Payment Notification), when the servlet starts up, in the init(), I starts the Swing runnable app which opens a desktop window, but 30 minutes later an error in the Swing caused the servlet to stop, how can that happen ? Because the runnable is running on it’s own thread, servlet started that thread, why an error in that thread will cause the servlet to stop ?
public class License_Manager extends JPanel implements Runnable
{
License_Manager()
{
Do_GUI();
...
start();
}
public static void main(String[] args)
{
// Schedule a job for the event-dispatching thread : creating and showing this application's GUI.
javax.swing.SwingUtilities.invokeLater(new Runnable() { public void run() { Create_And_Show_GUI(); } });
}
}
public class PayPal_Servlet extends HttpServlet
{
public void init(ServletConfig config) throws ServletException
{
super.init(config);
License_Manager.main(null);
}
protected void processRequest(HttpServletRequest request,HttpServletResponse response) throws ServletException,IOException
{
}
}
And besides the error don’t even have anything to do with my code, it looks like this :
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: 17 >= 0
at java.util.Vector.elementAt(Vector.java:427)
at javax.swing.DefaultListModel.getElementAt(DefaultListModel.java:70)
at javax.swing.plaf.basic.BasicListUI.paintCell(BasicListUI.java:191)
at javax.swing.plaf.basic.BasicListUI.paintImpl(BasicListUI.java:304)
at javax.swing.plaf.basic.BasicListUI.paint(BasicListUI.java:227)
at javax.swing.plaf.ComponentUI.update(ComponentUI.java:143)
at javax.swing.JComponent.paintComponent(JComponent.java:763)
at javax.swing.JComponent.paint(JComponent.java:1029)
at javax.swing.JComponent.paintChildren(JComponent.java:864)
at javax.swing.JComponent.paint(JComponent.java:1038)
at javax.swing.JViewport.paint(JViewport.java:747)
at javax.swing.JComponent.paintChildren(JComponent.java:864)
at javax.swing.JComponent.paint(JComponent.java:1038)
at javax.swing.JComponent.paintToOffscreen(JComponent.java:5124)
at javax.swing.BufferStrategyPaintManager.paint(BufferStrategyPaintManager.java:278)
at javax.swing.RepaintManager.paint(RepaintManager.java:1220)
at javax.swing.JComponent._paintImmediately(JComponent.java:5072)
at javax.swing.JComponent.paintImmediately(JComponent.java:4882)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:803)
at javax.swing.RepaintManager.paintDirtyRegions(RepaintManager.java:714)
at javax.swing.RepaintManager.seqPaintDirtyRegions(RepaintManager.java:694)
at javax.swing.SystemEventQueueUtilities$ComponentWorkRequest.run(SystemEventQueueUtilities.java:128)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)
Edit :
Thanks for all the replies, it seems starting a thread in init() is a bad idea, my original idea was, my Swing GUI app processes all the messages the servlet gets and writes to a folder and I can see the GUI working on the screen while the servlet gets the messages at the back end, they are related, so I run those two processes at the same time and starting the servlet will automatically starts the GUI for me too in the init(), now I may start those 2 processes separately so that no matter what happens to the GUI, the servlet won’t stop !
Seems definitely wierd. Saw something similar on sun (now oracle) forums. No good answer on it till now. But may be you can get a clue as it seems the same problem
Link http://72.5.124.102/thread.jspa?threadID=5339908&messageID=10469703