java compare method explanation

Question

   public int compare(Map.Entry<Integer,Integer> o1, Map.Entry<Integer,Integer> o2){
                if(o1.getValue() < o2.getValue() ){
                    return -1;
                }
                else if(o1.getValue() > o2.getValue()){
                    return 1;
                }
                else{ 
                        if(o1.getKey() < o2.getKey()){
                            return -1;
                        }else{
                            return 1;
                        }
                }
}


public int compare(Map.Entry<Integer,Integer> o1, Map.Entry<Integer,Integer> o2){

                if(o1.getValue() == o2.getValue()){
                    return (o1.getKey() - o2.getKey()); 
                }
                else{
                    return (o2.getValue() - o1.getValue());
                }

}

As per my understanding above two compare method should give same result but they are behaving differently.

Can somebody help to understand why are they different?

`but they are behaving differently`, how?, did you perform some tests, if so post them — Ramanlfc, Nov 16 '17 at 17:53
Did you trace through the methods in your IDE debugger? Where is the difference? What did you find? These are all questions you should ask yourself BEFORE posting here. — Jim Garrison, Nov 16 '17 at 17:54

score 4 · Answer 1 · answered Nov 16 '17 at 17:54

4

The first one doesn't correctly handle the case where both keys and values are equal.

The second one doesn't correctly handle overflow.

answered Nov 16 '17 at 17:54

Louis Wasserman

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Feeding the help vampires? – Jim Garrison Nov 16 '17 at 17:54
@JimGarrison Yes, and why wouldn't I? – Louis Wasserman Nov 16 '17 at 17:55

java compare method explanation

1 Answers1