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question on Strings

 
Ranch Hand
Posts: 39
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Assuming written inside main

String s1 = new String("amit");
System.out.println(s1.replace('m','r'));
System.out.println(s1);
String s3="arit";
String s4="arit";
String s2 = s1.replace('m','r');
System.out.println(s2==s3);
System.out.println(s3==s4);


Above program segment produces following output:
arit
amit
false
true

i thought it will be:
arit
amit
true
true

I thought that Strings 's2' and 's3' will be pointing to the same String literal "arit" in String constant pool. But its giving the output as false when s2 and s3 are compared with == operator. can anybody explain why?
 
Marshal
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Can the compiler work out whether the two Strings are the same? Go through the information required for the compiler to work out that s2 and s3 are identical, then you will see why it produces false.
 
Sheriff
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The methods in String that return another String reference usually create a completely new String object, and return a reference to this.

When using Strings, always use equals over == unless you've called intern() yourself:
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