Puzzling Exception

When I run my applet, it runs just fine. About once in maybe 20 launches, however, it throws the following exception. Even when this happens, it launches without any trouble, but it bothers me.

None of the objects referred to belong to my code - which is way to large to include here, and without a clue as to where this might be coming from it's hard to narrow things down.

Any ideas what may be causing this?

java.lang.IllegalArgumentException: null source

at java.util.EventObject.<init>(EventObject.java:34)

at java.awt.AWTEvent.<init>(AWTEvent.java:252)

at java.awt.event.ComponentEvent.<init>(ComponentEvent.java:94)

at java.awt.event.WindowEvent.<init>(WindowEvent.java:174)

at java.awt.event.WindowEvent.<init>(WindowEvent.java:211)

at java.awt.DefaultKeyboardFocusManager.dispatchEvent(DefaultKeyboardFocusManager.java:576)

at java.awt.Component.dispatchEventImpl(Component.java:3506)

at java.awt.Container.dispatchEventImpl(Container.java:1627)

at java.awt.Window.dispatchEventImpl(Window.java:1606)

at java.awt.Component.dispatchEvent(Component.java:3477)

at java.awt.EventQueue.dispatchEvent(EventQueue.java:480)

at java.awt.SequencedEvent.dispatch(SequencedEvent.java:93)

at java.awt.EventQueue.dispatchEvent(EventQueue.java:478)

at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatchThread.java:201)

at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:151)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:145)

at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:137)

at java.awt.EventDispatchThread.run(EventDispatchThread.java:100)

[1790 byte] By [paulmcarlislea] at [2007-10-2 21:46:05]
# 1
Some code to go along with the error might help.
Norweeda at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...
# 2

> Some code to go along with the error might help.

See above; the applet consists of roughly 25,000 lines of code scattered over a few dozen classes. The exception doesn't provide even a hint about what classes are involved - everything referenced seems to be Java-specific, and unrelated to my classes.

The fact that it only occurs once in several dozen runs doesn't help either, of course.

paulmcarlislea at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...
# 3
>Any ideas what may be causing this?It appears to be a focus issue.Have you searched for bug reports?
IanSchneidera at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...
# 4

I have searched for bug reports; it's hard to know what to look for, though. I will have a another look, this time focusing on focus.

It seems that this happens fairly frequently; since I've been testing my applet, I've gotten into the habit of leaving my Java console open all the time, and I see this same behavior on other applet-containing pages. As in my case, it is sporadic, and doesn't seem to prevent the applet from running. It's just that past, and often bitter experience have taught me to view such things suspiciously. And a surprising number of users watch the console and send exception reports and stack traces.

paulmcarlislea at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...
# 5
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5098165
quittea at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...
# 6
I guess these Exceptions caused by multi-thread.
wushi777.admina at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...
# 7
http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=5098165Looks like this is the problem; look like something I should ignore.Thank you.
paulmcarlislea at 2007-7-14 1:01:40 > top of Java-index,Java Essentials,Java Programming...