java - FindBug says this concurrent map doesnt need synchronized -


this question has answer here:

so i've discovered findbug, it's making me think don't know i'm doing in couple of places. 1 of them

private map<string, object> map = new concurrenthashmap<string, object>();  public void method1(){     synchronized(map){ // findbug says unnecessary         (string keys: map.keyset()){             ...         }     }         }

i thought needed synchronize iteration, or case of findbug not being smart enough realize it's necessary? want make sure!

the iterators concurrenthashmap "weakly consistent," meaning reflect state of map @ time iterator created may not reflect modifications made map after iterator created; in other words, iterator isn't going throw concurrentmodificationexception, don't need lock underlying map.


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