how does == operator work in java

Question

public class StrEqual {
    public static void main(String[] args) {
        String s1 = "hi";
        String s2 = new String("hi");

        System.out.println(s1);
        System.out.println(s2);

        if(s1 == s2){
            System.out.println("s1 and s2 are equal");
        }
        else{
            System.out.println("s1 and s2 are not equal");
        }
    }
}

In the above code s1 and s2 both referring to the string "hi". But why the output of the program is- 's1 and s2 are not equal' ? Thank you

@SotiriosDelimanolis how is this a duplicate of that? – forgivenson Apr 11 '14 at 20:11 — forgivenson, Apr 11 '14 at 20:11
Search for "java compare strings". – user2864740 Apr 11 '14 at 20:11 — user2864740, Apr 11 '14 at 20:11
It works exactly like `==`. – Adam Arold Apr 11 '14 at 21:07 — Adam Arold, Apr 11 '14 at 21:07

score 4 · Answer 1 · edited Apr 11 '14 at 20:13

4

Try

s1.equals(s2);

s1 == s2 compares the object references, not the string contents.

edited Apr 11 '14 at 20:13

Sotirios Delimanolis

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answered Apr 11 '14 at 20:10

Trevor

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score 0 · Answer 2 · answered Apr 11 '14 at 20:11

0

The == operator compares the object reference, i.e., their locations in memory. It's like comparing pointers. To have "deep" equality you need to use the equals method.

answered Apr 11 '14 at 20:11

Giovanni Botta

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how does == operator work in java

2 Answers2