WeakHashMap « Collections Data Structure « Java

1.To enable automatically release of the value, the value must be wrapped in a WeakReference object
2.Create a WeakHashMap with a single element in it
3.A WeakValueHashMap is implemented as a HashMap that maps keys to Weak Values
4.Implements a combination of WeakHashMap and IdentityHashMap
5.Weak ValueMap
6.Weak Valued HashMap
7.Weak Value HashMap
8.Weak Identity Map
9.A hashtable-based Map implementation with weak keys and using reference-equality in place of object-equality when comparing keys (and values).

10.A hash table with weak keys, full concurrency of retrievals, and adjustable expected concurrency for updates.
11.Map which stores items using SoftReference.