It's not entirely clear what you mean, but:
- You can have more than one VM (version / brand etc) installed on the same machine
- You can run more than one
java
process, whether of the same JVM version or different ones
Unless you're running a debugging agent or something similar, I don't know of any way to ask a JVM process whether it's loaded a particular class. It seems a bit of an odd requirement - why do you want to do this?
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