Is there java.util.concurrent equivalent for WeakHashMap?

Question

Can the following piece of code be rewritten w/o using Collections.synchronizedMap() yet maintaining correctness at concurrency?

Collections.sy         


        

Answer 1

Does wrapping the WeakHashMap in a synchronized map still work correctly for what you want to do, since the garbage collector can modify the weakreferences directly at anytime, bypassing the synchronized map wrapper? I think WeakHashMap only truly works in a single threaded model.

As mentioned above, the documentation for WeakHashMap at https://docs.oracle.com/javase/7/docs/api/java/util/WeakHashMap.html specifically says:

"A synchronized WeakHashMap may be constructed using the Collections.synchronizedMap method"

Which implies to me that this technique must work in tandem with the garbage collector's behavior (unless the documentation is buggy!)