On Sun, Nov 3, 2013 at 10:56 AM, Matt Benson <gudnabr...@gmail.com> wrote:
> Sounds like it would be trivial to frame what you've done here into the > context of a Weaver module, for which there exist both a maven plugin and > an Antlib, as well as a need for a near-term release. :-) > and eating our own dog food :) We may pushing the limits of Dajman's patience for a 1.0 which is long overdue. I suppose D needs to weigh using ASM or [weaver] vs. adjusting the current code with Java 5. Gary > > Matt > On Nov 3, 2013 2:30 AM, "Damjan Jovanovic" <dam...@apache.org> wrote: > > > On Fri, Oct 25, 2013 at 1:52 PM, Matt Benson <gudnabr...@gmail.com> > wrote: > > > > > On Oct 25, 2013 6:30 AM, "Damjan Jovanovic" <damjan....@gmail.com> > > wrote: > > > > > > > > On Fri, Oct 25, 2013 at 12:36 PM, Jörg Schaible > > > > <joerg.schai...@scalaris.com> wrote: > > > > > Hi Damjan, > > > > > > > > > > Damjan Jovanovic wrote: > > > > > > > > > > [snip] > > > > > > > > > > Thanks for explanation. > > > > > > > > > >> We would be able to adapt that for Java < 1.7 by swallowing the > > close > > > > >> exception instead of calling addSuppressed() on the primary > > exception, > > > > >> but the show stopper is catching and rethrowing the primary > > exception > > > > >> (Throwable), which javac < 1.7 refuses to compile because it > doesn't > > > > >> do "Rethrowing Exceptions with More Inclusive Type Checking" > > > > >> ( > > > > > > > > > http://docs.oracle.com/javase/7/docs/technotes/guides/language/catch-multiple.html > > > ). > > > > >> > > > > >> But this would work and always sets succeeded correctly without > > > > >> catch/re-throw: > > > > >> > > > > >> final InputStream is = factoryMethodThatCanThrow(); > > > > >> boolean succeeded = false; > > > > >> try { > > > > >> try { > > > > >> is.methodThatCanThrow(); > > > > >> } finally { > > > > >> } > > > > >> succeeded = true; > > > > >> } finally { > > > > >> closeSafely(!succeeded, is); > > > > >> } > > > > > > > > > > I guess the nested try was unintentionally ;-) > > > > > > > > > > Cheers, > > > > > Jörg > > > > > > > > Well that actually won't work, because the "succeeded = true;" will > be > > > > skipped if there is a "return;" in the inner try. > > > > > > > > Other than a custom Java compiler, I guess there's no clean way of > > > > doing this in Java < 1.7. There's really only option 2 - with being > > > > careful to always set succeeded correctly on all paths out of the try > > > > block. Almost like releasing memory in C. > > > > > > > > > > I haven't deeply followed this conversation, but would this be a > > candidate > > > for a [weaver] module? > > > > > > Matt > > > > > > > > > > [weaver] I am less sure about, but by playing with Objectweb's ASM I did > > manage to compile code with try-with-resources on Java 7, change the > class > > file version, do some bytecode manipulation to delete calls to > > Throwable.addSuppressed(), and get it to work on Java < 7. > > > > Made it into a Maven plugin and it works well :). Also verified other > Java > > 7 language features (binary literals, underscores in numeric literals, > > strings in switch, diamonds, exception multi-catch and re-throw) work on > > Java < 7 because they're just syntactic sugar. > > > > It's very small and simple - 143 lines in 1 file. Is it worth adding as a > > new commons project? Or do we not host (projects that contain) Maven > > plugins? > > > > Damjan > > > -- E-Mail: garydgreg...@gmail.com | ggreg...@apache.org Java Persistence with Hibernate, Second Edition<http://www.manning.com/bauer3/> JUnit in Action, Second Edition <http://www.manning.com/tahchiev/> Spring Batch in Action <http://www.manning.com/templier/> Blog: http://garygregory.wordpress.com Home: http://garygregory.com/ Tweet! http://twitter.com/GaryGregory
