What happens if the Jar is updated while it is still in use by the JVM?

Question

I know that in typical conditions a class is loaded only once. I also know that classes are immutable. Thus, once the class is loaded, it cannot be changed unless it is reloaded (which usually does not happen).

Is the same true for Jars? What happens if the Jar updates while the JVM is still running, which previously loaded classes from the Jar?

Answer 1

Nothing, if a class is used in this bank, the same definition remains, if a new class is loaded into the updated bank, this will be done.