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Unique JVM identifier

Ed Ward
Ranch Hand

Joined: Jan 30, 2006
Posts: 147
Greetings all!

Given a single computer running two JVM instances which have been started with identical configurations and command line properties, is there any attribute or environment property which uniquely identifies a given JVM instance?

I thought maybe looping through System.getenv(), but I do not see anything there which identifies the JVM instance.

I found this from awhile back but was wondering if maybe things have changed:

Can an application determine the JVM instance?

Thanks in advance!
Rob Spoor

Joined: Oct 27, 2005
Posts: 19651

There is one unique identifier - the process ID. You can't get this without JNI though, and unique only means unique at that moment. Nothing prevents the system from reusing your JVM process ID for another process after the JVM has shutdown.

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