I need to try a problem in someone else's head. Basically, does the Sun JVM like to open and close a .jar file multiple times it is running a class from?

The situation is this: we have a batch process in Java that is kicked off by cron every ten minutes. It is run from a completely self-contained JAR file. We had a release this morning that replaced that file and the process fell over with two ClassNotFound errors. Yet both classes (part of Hibernate) are actually in the jar. And the process ran normally when it was run again 10 minutes later.

We figured that the file was replaced as the JVM was loading classes. But that means it opens and closes the file repeatedly. Is that consistent with what you guys have seen?

Wade.