Question

Possible Duplicate:
Questions about Java's String pool

String s1 = "length";
String s2 = "length";
System.out.println("EQUAL: " + (s1 == s2));
String s3 = "length: 10";
String s4 = "length: " + s3.length();
System.out.println(s3.length());
System.out.println(s4.length());
System.out.println("EQUAL: " + (s3 == s4));

Output :

EQUAL: true //Understood same string reference in string pool

10

10

EQUAL: false // Why?

Answer 1

 String s4 = "length: " + s3.length();

Creates new String object.

So, s3 reference to different object and s4 references to different object, which makes == condition return false.