I can confirm that the JDK team /has/ committed the change to restore Reflection.getCallerClass() in Java 7u40:
http://hg.openjdk.java.net/jdk7u/jdk7u40-dev/jdk/rev/244dbaeab45e So, hurray! Lol. Nick On Aug 1, 2013, at 9:48 AM, Remko Popma wrote: > O(n log n) would not be too bad, but what you're describing sounds more like > quadratic time! > That's huge, Nick, congrats! That would mean a big speed improvement for the > location-based layout patterns in Log4j, they use > Thread.currentThread().getStackTrace() under the hood. Nice! > > -Remko > > From: Nick Williams <nicho...@nicholaswilliams.net> > To: Log4J Developers List <log4j-dev@logging.apache.org> > Sent: Thursday, August 1, 2013 10:11 PM > Subject: Re: Relfection.getCallerClass > > Here's something interesting. > > So the last method I had to write, StackTraceFrame.getStackTrace(Throwable), > I finished last night. It's the alternative to Throwable.getStackTrace(). > Instead of returning StackTraceElement[] (String for declaring class name), > it returns StackTraceFrame[] (Class<?> for declaring class). I expected this > to perform about the same or possibly even worse--boy was I wrong. > > StackTraceFrame.getStackTrace(Throwable) consistently returns in half the > time that Throwable.getStackTrace() does. Looking at why that is, I found a > HUGE inefficiency in Throwable.getStackTrace(). > StackTraceFrame.getStackTrace(Throwable) walks the backtrace 1 time and runs > O(n), where n is the number of elements in the stack trace. > Throwable.getStackTrace() walks the back trace 1+(n/2) times (first it > measures the depth of the back trace in one native method call, then it gets > the elements by index in a native method call for each, looping up to that > index each time), for an O(nlogn) (I think) running time. Much worse. > > So ... I improved Throwable.getStackTrace() and cut its running time in half > while I was at it. This also resulted in cutting > Thread.currentThread().getStackTrace()'s runtime in half. Think they'll > appreciate it? :-/ > > N > > On Jul 31, 2013, at 4:42 PM, Paul Benedict wrote: > >> http://mail.openjdk.java.net/pipermail/core-libs-dev/2013-July/019486.html >> >> >> On Wed, Jul 31, 2013 at 4:40 PM, Gary Gregory <garydgreg...@gmail.com> wrote: >> Hm... do you have a URL for this ray of hope? >> >> Gary >> >> >> On Wed, Jul 31, 2013 at 5:34 PM, Paul Benedict <pbened...@apache.org> wrote: >> Nevermind. I just found it. Lousy browser caching! >> >> >> On Wed, Jul 31, 2013 at 4:33 PM, Paul Benedict <pbened...@apache.org> wrote: >> Did you find this out on the OpenJDK mailing list? I can't find the >> information; I may have missed it. >> >> >> On Wed, Jul 31, 2013 at 4:22 PM, Gary Gregory <garydgreg...@gmail.com> wrote: >> KA-POW! Well done, sir. How about we use your mug as the new logo? ;) >> >> Gary >> >> >> On Wed, Jul 31, 2013 at 4:47 PM, Nick Williams >> <nicho...@nicholaswilliams.net> wrote: >> A PARTIAL VICTORY! >> >> They've decide to revert the change to Reflection.getCallerClass for 7u40 >> and the rest of 7. Woohoo! >> >> "What will happen to this method in JDK 8 requires further thought." >> >> Meanwhile, about 300 lines of Java and 1,000 lines of native code later, I'm >> about ready to submit my patch for a public API replacement in Java 8. >> >> N >> >> On Jul 29, 2013, at 8:39 AM, Gary Gregory wrote: >> >>> What a mess :( it seem unlikely new APIs will be added to Java 8 to help >>> us, at least based on comments like >>> http://mail.openjdk.java.net/pipermail/core-libs-dev/2013-July/019110.html >>> >>> We might be left with documenting our side with "if you use features x and >>> y in this context then the speed will degrade to so and so, here is where >>> to ask Oracle to fix it: http:..." >>> >>> Gary >>> >>> On Jul 29, 2013, at 9:06, Nick Williams <nicho...@nicholaswilliams.net> >>> wrote: >>> >>>> core-libs-dev >> >> >> >> >> -- >> E-Mail: garydgreg...@gmail.com | ggreg...@apache.org >> Java Persistence with Hibernate, Second Edition >> JUnit in Action, Second Edition >> Spring Batch in Action >> Blog: http://garygregory.wordpress.com >> Home: http://garygregory.com/ >> Tweet! http://twitter.com/GaryGregory >> >> >> >> -- >> Cheers, >> Paul >> >> >> >> -- >> Cheers, >> Paul >> >> >> >> -- >> E-Mail: garydgreg...@gmail.com | ggreg...@apache.org >> Java Persistence with Hibernate, Second Edition >> JUnit in Action, Second Edition >> Spring Batch in Action >> Blog: http://garygregory.wordpress.com >> Home: http://garygregory.com/ >> Tweet! http://twitter.com/GaryGregory >> >> >> >> -- >> Cheers, >> Paul > > >
