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Not just the time, but the environment, the OS as well. Where you can run JVM, there's a pretty good chance you can run your app.

If your app requires a specific JDK version and your OS wont support, you can run that JDK version in a modern JVM: https://www.graalvm.org/latest/reference-manual/espresso/

That's important since this capability has been removed from OpenJDK a long time ago.