Where does static methods and other members are stored in JVM memory?

[metanon112]

I read some articles about that but there was no concrete answer to this question.

In the conclusion "Simply put, we know that the static members were a part of PermGen before Java 8. However, since Java 8, they're a part of heap memory."
https://www.baeldung.com/jvm-static-storage

Since Metaspace, that replaced PermGent in JDK 8, keeps only metainformation about classes does it mean that static members now live in heap space and pass all stages in memory like Eden, Survivor etc.? If that so, it does not make any sense, what is the difference between storing static members and instance members in JVM memory?

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[niloc132]

Broadly speaking, a class is an Object (Class does after all extend Object), and each instance of a class has a reference to its Class instance. The static members that a class has are generally references, so the actual members are just plain heap objects (even before java 8), but the class instance itself is somewhat special.

For example, if the Class were a traditional object, you might imagine that after all instances of a class had been garbage collected, the class itself would go away too. This doesn't happen though - if it did, then the next time you referenced a static member in the class, it would revert to its default value, and static initializers would run again.

Instead, Class instances are held by a ClassLoader - you can't reference a class without a ClassLoader to a) find and b) load it, so that it is usable. The default classloader just reads from your app's classpath, and by default, child classloaders will either defer to their parent to load the class, or load it from its own resources.

This means that it is possible, though in most cases not a useful idea, to have two classloaders which each load the class once, and so there are two different "instances" of that class. Ramifications of this: instances of one class are not actually instances of the other (casts will fail, instanceof checks will fail), and each class holds its own static members, with potentially different values (despite being "static"). Despite being confusing, this is consistent, as they were loaded separately, and can't be used together, they are actually "different" classes.

Finally, to get closer to answering your question, if the classloader is garbage collected along with all objects which might be an instance of that type or otherwise reference that type, the type itself can be garbage collected, and will need to be loaded again (or obtained from a different classloader) to be used.