Comma Operator in Java Example

There will be times when we will want to include more than one statement in the initialization and iteration sections of the For loop. For example, consider the loop in the following program:

class CommaOperator 
 { 
             public static void main(String args[] ) 
             { 
                         int i,j; 
                         for(i=1,j=20;j>=10;i++,j-=2) 
                         { 
                                     System.out.println(i+"  "+j); 
                         } 
             } 
 }

The value of variable i and j are set to 1 and 20 respectively in the for loop using comma operator. Since, the logical expression j >=10 is true (value of j = 20), body of the for loop will execute displaying the values i and j as 1 and 20 respectively on the screen. The value of i will be then incremented and the value of j will be decremented by 2. So, the next value displayed will be 2 and 18. The loop will execute for the time the logical expression j>=10 is true. In Java, the comma operator is applied only to the for loop.