In java "string" == "string" is false why? -

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the following statement appears in section 3.10.5. string literals of java language specification:

a string literal refers same instance of class string. because string literals - or, more generally, strings values of constant expressions (§15.28) - "interned" share unique instances, using method string.intern.

i using java jdk 7 , eclipse indigo.

and test program follows:

public class main {      public static void main(string[] args) {         string s1 = "string";         string s2 = "string";          system.out.print(s1 == s2); // true         system.out.print(" , " + "string" == "string"); // false     }  }

this operator precedence issue. == operator has lower precedence + operator.

what testing whether (" , " + "string") equal "string". isn't.

if mean compare "string" , "string" should write:

    system.out.print(" , " + ("string" == "string"));

the standard advice of not using == test strings applies ... that's not giving confusing output.


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