There is a rather bad bug in commons-launcher-0.9. Its bad if you want to get notified when the child JVM dies because of an Error (like java.lang.OutOfMemoryError). I need such information because I am using Java Service Wrapper,
http://wrapper.tanukisoftware.org/doc/english/, which allows one to wrap their java code in a platform specific native wrapper which, for example, detects the printing of the string "java.lang.OutOfMemoryError" by the child JVM and restarts the child (if thats the behavior you want). Its a rather perfect fit with commons-launcher; I use the wrapper to launch the launcher and all of the java classpath, system properties, etc. variability is located in the java application specific launcher.xml file. Any way, the bug: When the child java application has an Error thrown, it propagates up the thread stack until it reaches the ThreadGroup class ExitOnErrorThreadGroup, which is a commons-launcher class. Here the ThreadGroup method, public void uncaughtException(Thread t, Throwable e) Is redefined to call the Launcher code to print out the Error object's information. Specifically, it calls, Launcher.error(Throwable e); Well, two problems. The first, and less serious, the parent java process, the one that executed ChildMain as a child java process, actually initialized the Launcher class' log - the child java process never initialized its own copy of the Launcher class' log. So if one expects the error message to go to the same place as the parent process' log - mayby it will maybe it won't. The second is a more serious problem. When the child java process gets to calling Launcher.error(e) for the first time, well this is the first time that the Launcher class has been loaded by the child process so it and all objects it depends upon must be loaded. Well, it uses Ant's project class so basically, the child process has to have Ant in its class path. If it does not, then the Error message is NEVER printed because a different exception is thrown while the JVM is trying to load the Ant class (since it can not find them since they are not on the classpath). If the Error message is NOT printed, then the Java Service Wrapper never sees the message and the Java application is not restarted - which is why I discoved the bug in the first place after some searching around. The solution: Recommending that users of the commons-launcher allways include Ant in their class path I think is a no starter. The solution I would like is for the ExitOnErrorThreadGroup class' uncaughtException(..) method simply to print the Error message to System.err. Thanks RME --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
