The code below demonstrate how to use the while loop statement. The while statement will check if its expression evaluates to true and execute the while statement block.

The program below will execute while the countDown value is bigger or equals to zero.

package org.kodejava.basic;

public class WhileDemo {
    public static void main(String[] args) {
        // Start the count-down from 10
        int countDown = 10;

        // Do the count-down process while the value of
        // countDown is bigger or equals to zero.
        while (countDown >= 0) {
            System.out.println(countDown);
            countDown--;

            try {
                // Adds one-second delay.
                Thread.sleep(1000);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}