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I have a class which I want to set up as keys in HashMap. I already have implemented the compareTo method for that class. But still when I do:
map.put(new MyKey(dummyArguements) , dummyValue ); System.out.println(map.get( new MyKey(dummyArguements) ) );
I get null.
So that means hashmap is not able to identify that the two keys (for get & put call) are same.
Could someone help me here please ?
You need to implement
hashCode()andequals().compareTo()is additionally required for sorted map/set.See this question for details.