On Fri, May 24, 2013 at 6:18 AM, Alan Bateman <alan.bate...@oracle.com>wrote:
>
> The webrev with the proposed changes is here. As I mentioned in one of the
> replies, there are 4 j.u.c tests that need to be updated so I've changed
> these tests to use Unsafe.throwException.
>
Alan, you're telling everyone there's no need for Thread.stop, but you are
replacing usages in tests with calls to Unsafe, which is not available to
normal code. So you have a kind of moral obligation here to replace usages
with "ordinary" java code. There are other ways to do sneakyThrow, and
perhaps a sneakyRethrow method should be added to the jdk test library.
Ordinary java code should be able to simply catch and rethrow a Throwable
if type analysis can "prove" that the exception is not an Exception.
As a data point, Doug uses this:
(Doug, it's not obvious to me why you handle Error and RuntimeException
specially)
/**
* A version of "sneaky throw" to relay exceptions
*/
static void rethrow(final Throwable ex) {
if (ex != null) {
if (ex instanceof Error)
throw (Error)ex;
if (ex instanceof RuntimeException)
throw (RuntimeException)ex;
ForkJoinTask.<RuntimeException>uncheckedThrow(ex);
}
}
/**
* The sneaky part of sneaky throw, relying on generics
* limitations to evade compiler complaints about rethrowing
* unchecked exceptions
*/
@SuppressWarnings("unchecked") static <T extends Throwable>
void uncheckedThrow(Throwable t) throws T {
if (t != null)
throw (T)t; // rely on vacuous cast
}
