Unexpected Output of System.out.print statement

Question

When used String's intern method in program it gives some unexpected output i'm unable to understand why this gives such output

public class Test {

    public static void main(String[] args)
    {

        String str1 = "patty";
        String str2 = new String("patty");

        System.out.println("1   ->  "+ str1 == str2);

        String str3 = str2.intern();

        System.out.println("2   ->  "+ str1 == str3);
    }
}

in output it shows

false
false

but the expected output is

1   ->  false
2   ->  true

Can anyone please help me to understand this problem

i'm just trying to compare two references using intern method so i used == insted of .equals — vishal s., Nov 19 '19 at 10:35
It is really well explained in this article https://www.geeksforgeeks.org/interning-of-string/ — Sergio Arrighi, Nov 19 '19 at 10:36

Eran · Accepted Answer · 2019-11-19T10:37:06.140

2

Even though str1 and str3 reference the same String instance, you are not comparing these references.

System.out.println("2   ->  "+ str1 == str3);

compares "2 -> "+ str1 to str3.

Try:

System.out.println("2   ->  "+ (str1 == str3));

edited Nov 19 '19 at 10:37

answered Nov 19 '19 at 10:34

Eran

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ok got it thank you – vishal s. Nov 19 '19 at 10:36
@vishals. you need to accept the answer if it answered your question, so that others know it's been answered. – ahoxha Nov 19 '19 at 10:41
yes i will accept it but before 10 minutes i can't accept it so i will accept it in 10 minutes after answered – vishal s. Nov 19 '19 at 10:43

Unexpected Output of System.out.print statement

1 Answers1