In a Map we can lookup for a value by using a distinct key. In a Map with reverse view and lookup, even the values are distinct. So there is one to one mapping between keys and values and vice version.

If we enable this constraint on a Map then we can look up a key by its value. Such data structure is called bi directional map.

There is no built data structure similar to reverse lookup Map in JDK.

But Apache Common Collections and Guava libraries provide implementation of bidirectional map. It is called BidiMap and BiMap. Both of these data structure enforce the constraint of one to one mapping between keys and values.