Can I run more than one JVM? If yes then how can I find a particular class is loaded on which JVM?
You can run as many JVMs as you can fit on your disk and in memory :)
Whenever you start a Java application, you're first starting the JVM and then telling it which application to run. The answer to "which JVM" is simply: The JVM that you loaded the application with!
It's possible to do some esoteric fiddling with classloaders which would prove an exception to what I've just said. But it's true in the general case and the majority of all applications.