CODEWITHSUNDEEP
javacollectionshashmapiteration
flyleaf
flyleaf

Reputation: 995

how to remove an entry from hashmap by checking its value?

I have a java map with string in its key and integer in its value. I want to remove a particular entry(key/value) from this map which doesn't have value greater than 5. Can any body suggest me how can I do this?

Thanks!

Upvotes: 1

Views: 1071

Answers (2)

flyleaf
flyleaf

Reputation: 995

Ok! I did the job as following. Thanks to Stephen C:

Iterator<Map.Entry<String,Integer>> iter = TestMap.entrySet().iterator();
while (iter.hasNext()) {
    Map.Entry<String,Integer> entry = iter.next();
    if(entry.getValue() <= 5){
        iter.remove();
    }
}

Upvotes: 1

Stephen C
Stephen C

Reputation: 718788

If you've only got a regular map (i.e. no additional data structure that implements a reverse mapping), then your best option is to iterate the value set, test each value, and use Iterator.remove() to remove the relevant ones.

If you have a secondary data structure, you may be able to use it to identify the entries to be removed. But the "cost" is that such a data structure takes space to represent and time to update ... and your code is more complex.

Upvotes: 4

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