Do loop: This is one of Java's three control structures employed for looping. The other two are the for loop and while loop. A do loop comprises of a loop body and a Boolean expression. The condition is tested subsequent to the loop body has been finished for the very first time and re-tested each and every time the end of the body is finished. The loop terminates whenever the condition offers the value false. The statements in the loop body will for all time be performed at least once.