differences between the == operator and the equals() method in Java

Equals method compare values of the receiver and sender object. It returns true if the values are same. While ‘==’ operator is a fundamental operator, it compares reference of the sender and receiver object. E.g.

String s1 = "Hello";
String s2 = "Hello";
String s3 = new String("Hello");
System.out.println(s1 == s2); // true
System.out.println(s1 == s3);// false
System.out.println(s1.equals(s2));// true
System.out.println(s1.equals(s3));// true

From the example, we can see that reference and value for s1 & s2 are same. At the same time s3 is a newly created instance which has same value as of s1 and s2 but reference is different.

September 27, 2008 | Filed Under Java