We have a Java web app that uses javaws. It will run fine under Java 8 update 40, but under Java 8 update 51 jp2launcher.exe just stops, without launching the application.
- I have found the logs in C:\Users\me\AppData\LocalLow\Sun\Java\Deployment\log but they're identical between j8u40 and j8u51 (except of course for the order jars are loaded, the jre version and the launch time).
- I have logged the launch using Process Monitor, for both jre versions. Under j8u51, jp2launcher.exe just exits with the result "SUCCESS". Comparing the two procmon logs, I can't pick out anything unusual. They both rummage through the C:\Users\me\AppData\LocalLow\Sun\Java\Deployment directory and their respective C:\Program Files\Java\jre1.8.0_XX\lib directories and such like, but then the j8u51 one just exits.
- The Windows event logs don't show anything Java related.
- I have managed to run the jnlp with set "JAVAWS_VM_ARGS=-Xcheck:jni -XX:-TraceClassLoadingPreorder -XX:+PrintCommandLineFlags -verbose:jni -verbose:class -verbose:gc -XX:+PrintGCDetails -Djava.util.logging.config.file=C:\misc\logging.properties" and log the stdout/stderr. It looks like javaws and jp2launcher log to the output, then both jre8u40 and jre8u51 versions terminate. Presumably in the j8u40 version it is launching another jp2launcher.exe to run the application.
- Comparing the two output logs yields nothing of interest. The classes are loaded in nearly identical order, mostly identical classes other than a few differences that are easily explained by just being more up-to-date classes being used.
- Finally, I have been able to launch the application directly, using java.exe, by obtaining the client files from the server install and unpacking them. The app itself runs just fine under jre8u51, so the problem definitely lies with javaws itself.
I can find very little documentation on the inner workings of Java Web Start, and no documentation at all on jp2launcher.exe. Can anyone suggest what might be going wrong here, or other diagnostic steps I can take?
e: sorry for the strange username. I've tried changing it in my profile, but the forums don't seem to want to accept the change...