What are the differences between while loop and do-while loop in Java?

JavaObject Oriented ProgrammingProgramming

The while loop in java executes one or more statements after testing the loop continuation condition at the start of each iteration. The do-while loop, however, tests the loop continuation condition after the first iteration has completed. Therefore, the do-while loop guarantees one execution of the loop logic whereas the while does not.


public class WhileAndDoWhileLoop {
   public static void main(String args[]) {
      int i=5;
      System.out.println("Test while Loop:");
      while(i < 5) {
         System.out.println("Iteration: "+ ++i);
      System.out.println("Test do-while Loop:");
      do {
         System.out.println("Iteration: "+ ++i);
      } while(i < 5);

In the above example, The while loop statement will not execute at all. However, one iteration of the do-while loop will execute.


Test while Loop:
Test do-while Loop:
Iteration: 6
Updated on 24-Feb-2020 10:58:37