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NoClassDefFoundError in sun.misc. Unsafe.ensureClassInitialized

Steve Leach
Ranch Hand

Joined: Sep 24, 2003
Posts: 46
Hi again all, here's my latest challenge...
While trying to run a report (using Jasper reports) on my new server I am getting a NoClassDefFoundError thrown by sun.misc.Unsafe.ensureClassInitialized().
I have included a full stack trace below, but it looks like the de-serializer is not finding one of the classes that was serialized when compiling the report.
So far so good.
The problem I have is that the exception has no message, and therefore I have no way of knowing which class it cannot find.
I have checked the javadoc for NoClassDefFoundError and it seems that there are no other methods that might provide the information about which class (which seems a strange ommission - you would have thought there would be a "getUnfoundClassName" method or something).
Does anyone have any suggestions on how I can track down the missing class ?
Please respond, even if only to say "no idea mate, sorry!".
William Brogden
Author and all-around good cowpoke

Joined: Mar 22, 2000
Posts: 13027
Since it says "native method" in

I am wondering if there is a DLL that it is looking for.
Steve Leach
Ranch Hand

Joined: Sep 24, 2003
Posts: 46
Not a bad suggestion, except that it's running on a Linux system. I had a problem the other day because the X-Window libraries weren't installed, and that reported a problem in a different native method. It was a "library not found" error rather than a "class not found" error though.
The other issue is that, even if it is a missing library, I have no way to know which one is missing.
I agree. Here's the link:
subject: NoClassDefFoundError in sun.misc. Unsafe.ensureClassInitialized
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