NullPointerException in JFileChooser

From:

Philipp <sicsicsic@freesurf.ch>

Newsgroups:

comp.lang.java.programmer

Date:

Mon, 07 May 2007 17:08:08 +0200

Message-ID:

<1178550458_2602@sicinfo3.epfl.ch>

Hello,
I have a method which shows a JFileChooser to select a save name. After
click on the dialog's OK button, _sometimes_ it throws NullPointerException.
I have checked the thread, and everything runs in EDT, so this should
not be the problem.

The calling code is
------------------
public File getSelectedFile() {
   chooser = new
JFileChooser(prefs.get(Configuration.KEY_LAST_SAVED_DIR, null));

   chooser.setSelectedFile(new File(defaultFileName));

   for(ExtensionFileFilter f : fileTypes){
     chooser.addChoosableFileFilter(f);
   }

   if (defaultFilter == null) {
     chooser.setFileFilter(chooser.getAcceptAllFileFilter());
   } else {
     chooser.setFileFilter(defaultFilter);
   }
// That's where it happens
   int returnVal = chooser.showSaveDialog(parentComponent);
//
prefs.put(Configuration.KEY_LAST_SAVED_DIR,chooser.getCurrentDirectory().getAbsolutePath());
   return chooser.getSelectedFile();
}
-----------------

Can you help me spot where the problem is?
The stack trace is below.

Thanks for any suggestions.
Philipp

Exception occurred during event dispatching:
java.lang.NullPointerException
    at javax.swing.JComponent.repaint(JComponent.java:4728)
    at sun.swing.FilePane$2.repaintListSelection(FilePane.java:114)
    at sun.swing.FilePane$2.repaintSelection(FilePane.java:104)
    at sun.swing.FilePane$2.focusLost(FilePane.java:99)
    at java.awt.AWTEventMulticaster.focusLost(AWTEventMulticaster.java:213)
    at java.awt.Component.processFocusEvent(Component.java:5930)
    at java.awt.Component.processEvent(Component.java:5794)
    at java.awt.Container.processEvent(Container.java:2058)
    at java.awt.Component.dispatchEventImpl(Component.java:4410)
    at java.awt.Container.dispatchEventImpl(Container.java:2116)
    at java.awt.Component.dispatchEvent(Component.java:4240)
    at
java.awt.KeyboardFocusManager.redispatchEvent(KeyboardFocusManager.java:1848)
    at
java.awt.DefaultKeyboardFocusManager.typeAheadAssertions(DefaultKeyboardFocusManager.java:878)
    at
java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:551)
    at java.awt.Component.dispatchEventImpl(Component.java:4282)
    at java.awt.Container.dispatchEventImpl(Container.java:2116)
    at java.awt.Component.dispatchEvent(Component.java:4240)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
    at
java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
    at
java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
    at
java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:177)
    at java.awt.Dialog$1.run(Dialog.java:1039)
    at java.awt.Dialog$3.run(Dialog.java:1091)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.awt.Dialog.show(Dialog.java:1089)
    at javax.swing.JFileChooser.showDialog(JFileChooser.java:723)
    at javax.swing.JFileChooser.showSaveDialog(JFileChooser.java:651)
    at io.FileSaver.getSelectedFile(FileSaver.java:141)
    at io.SaverManager.<init>(SaverManager.java:96)
    at io.SaverHolder$SaveSelector.actionPerformed(SaverHolder.java:153)
    at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1995)
    at
javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2318)
    at
javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:387)
    at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:242)
    at
javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
    at java.awt.Component.processMouseEvent(Component.java:6038)
    at javax.swing.JComponent.processMouseEvent(JComponent.java:3260)
    at java.awt.Component.processEvent(Component.java:5803)
    at java.awt.Container.processEvent(Container.java:2058)
    at java.awt.Component.dispatchEventImpl(Component.java:4410)
    at java.awt.Container.dispatchEventImpl(Container.java:2116)
    at java.awt.Component.dispatchEvent(Component.java:4240)
    at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4322)
    at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3986)
    at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3916)
    at java.awt.Container.dispatchEventImpl(Container.java:2102)
    at java.awt.Window.dispatchEventImpl(Window.java:2429)
    at java.awt.Component.dispatchEvent(Component.java:4240)
    at java.awt.EventQueue.dispatchEvent(EventQueue.java:599)
    at
java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
    at
java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
    at
java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
    at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
    at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)