java - How to remove elements of one map from another map? - 


hashmap<string, string> foo = new hashmap<string, string>(); hashmap<string, string> baar = new hashmap<string, string>();

how remove items found in baar foo?

you can try:

foo.keyset().removeall(baar.keyset())

changes map's keyset() reflected in map itself.

if want remove exact mappings (not based on keys), can use same approach entryset() instead:

foo.entryset().removeall(baar.entryset());

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