Difference between equals and == operator in Java

// Program to explain the following String function :
// equals versus ==
class  MequalsVersusEqualto
{
public static void main( String args[ ] )
{
 boolean b;
 String s1 = "JAVA";
 String s2 = "JAVA";
 String s3 = "Java";
 String s4 = new String( "JAVA" );
 String s5 = new String( "JAVA" );
 
 System.out.println( s1 + " equals " + s2 + " = " + s1.equals( s2 ) );
 System.out.println( s1 + "   ==   " + s2 + " = " + ( s1 == s2 ) );
 System.out.println( s1 + " equals " + s3 + " = " + s1.equals( s3 ) );
 System.out.println( s1 + "   ==   " + s3 + " = " + ( s1 == s3 ) );
 System.out.println( s1 + " equals " + s4 + " = " + s1.equals( s4 ) );
 System.out.println( s1 + "   ==   " + s4 + " = " + ( s1 == s4 ) );
 System.out.println( s4 + " equals " + s5 + " = " + s4.equals( s5 ) );
 System.out.println( s4 + "   ==   " + s5 + " = " + ( s4 == s5 ) );
}
}

Output:
 JAVA equals JAVA = true
 JAVA   ==   JAVA = true
 JAVA equals Java = false
 JAVA   ==   Java = false
 JAVA equals JAVA = true
 JAVA   ==   JAVA = false
 JAVA equals JAVA = true
 JAVA   ==   JAVA = false