Re: can't throw
On 09/13/2012 12:10 AM, Daniel Pitts wrote:
On 9/12/12 2:24 PM, Robert Klemme wrote:
there is no point in throwing from Thread.run()
or Runnable.run() other than catastrophic failures (all Errors such as
OOM, all RuntimeExceptions which are really programmer mistakes) because
you cannot customize handling of exceptions thrown from the run()
method: this method is only invoked from class Thread and probably
others in the Java standard library itself.
Actually, you can handle exceptions from a Thread. There is the
UncaughtExceptionHandler:
<http://docs.oracle.com/javase/7/docs/api/java/lang/Thread.UncaughtExceptionHandler.html>
Though the only valuable use I have ever seen from this is in logging
those failures differently than the default output.
Right, I completely forgot about that. The issue with this is that you
have far less context than inside method run(). So handling there is
certainly preferred.
Instead, you should be
handling exceptions in run() and terminate the thread gracefully (i.e.
by returning from run()).
Agreed. If you need some other code to propagate an Exception, you need
to pass that information along. Exceptions are meant to unwind the
stack. For most practical purposes a Thread's run() method really has no
stack to unwind. Even if you could throw an Exception from it, where
would that Exception go? Who's going to deal with it?
.... other than the default uncaught exception handler. Exactly.
Kind regards
robert