#1 NullPointerException when the DownloadDialog is resized

[Daniel Léonard]

During a mailbox download, when it downloads the
headers, if the dialog is resized, sometimes a
NullPointerException occurs.

It is very hard to reproduce, but sometimes it occurs.

In the stack trace, all the methods are from the standard
library. Maybe the bug is a bug in the look&feel or in
thelibrary itself.

If there is a place where it can go wrong, it is in
ProgressDialog in the method change(String text, int
value). It is also to note that the JProgressBar is
accessed in the event dispatching thread.

Here is the stack trace :
java.lang.NullPointerException
at javax.swing.plaf.basic.BasicProgressBarUI.
sizeChanged(BasicProgressBarUI.java:961)
at javax.swing.plaf.basic.BasicProgressBarUI.
getBox(BasicProgressBarUI.java:374)
at javax.swing.plaf.basic.BasicProgressBarUI.
setAnimationIndex(BasicProgressBarUI.java:905)
at javax.swing.plaf.basic.BasicProgressBarUI.
incrementAnimationIndex(BasicProgressBarUI.java:994)
at javax.swing.plaf.basic.
BasicProgressBarUI$Animator.
actionPerformed(BasicProgressBarUI.java:1265)
at javax.swing.Timer.fireActionPerformed(Timer.
java:271)
at javax.swing.Timer$DoPostEvent.run(Timer.java:
201)
at java.awt.event.InvocationEvent.
dispatch(InvocationEvent.java:178)
at java.awt.EventQueue.dispatchEvent(EventQueue.
java:448)
at java.awt.EventDispatchThread.
pumpOneEventForHierarchy(EventDispatchThread.java:
197)
at java.awt.EventDispatchThread.
pumpEventsForHierarchy(EventDispatchThread.java:
150)
at java.awt.EventDispatchThread.
pumpEvents(EventDispatchThread.java:144)
at java.awt.EventDispatchThread.
pumpEvents(EventDispatchThread.java:136)
at java.awt.EventDispatchThread.
run(EventDispatchThread.java:99)