Logging uncaught exceptions in threads created by third-party code in web application

Question

I suspect a thread created by a third-party jar used by my web application may be throwing an exception, and not catching it. However, I don't see any evidence of this in the log files. How can I force all uncaught exceptions to be dumped to a log file? This is for a web app running inside Glassfish.

Answer 1

It turns out that this is not necessary with Glassfish, because Glassfish already does it - but I was looking at the wrong place in the logs.

The exception was printed to the main server.log file - not to my application's own log4j log file.

Answer 2

You can change the uncaught exception handler.

http://docs.oracle.com/javase/7/docs/api/java/lang/Thread.UncaughtExceptionHandler.html

http://www.javapractices.com/topic/TopicAction.do?Id=229

Answer 3

You can set a default uncaught exception handler using Thread's setDefaultUncaughtExceptionHandler static method:

Thread.setDefaultUncaughtExceptionHandler( new Thread.UncaughtExceptionHandler() {
            public void uncaughtException( final Thread t, final Throwable e ) {
                ...