How to clear the entry from String Literal Pool [duplicate]

Answer 1

String literals (WeakHashMap) are also stored in heap memory called the "permgen" heap. need to configure in JVM to find and collect dynamically loaded classes that are no longer needed, and this may cause String literals to be garbage collected. and or when JVM performas the Full gc.

Answer 2

An excerpt from How does Java store Strings and how does substring work internally?:

Strings in the pool can be garbage collected (meaning that a string literal might be removed from the pool at some stage if it becomes full)