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From: Robert Klemme <shortcutter@googlemail.com>
Newsgroups: comp.lang.java.programmer
Subject: Re: can't throw
Date: Thu, 13 Sep 2012 23:32:20 +0200
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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