while Loops

The while loop does not have as many different sections to set up as the for loop. The only thing it needs is a conditional test, which accompanies the while statement. The following is an example of a while loop:

while (gameLives > 0) {
 // the statements inside the loop go here
}


This loop will continue repeating until the gameLives variable is no longer greater than 0. The while statement tests the condition at the beginning of the loop, before any statements of the loop have been handled. For this reason, if the tested condition is false when a program reaches the while statement for the first time, the statements inside the loop will be ignored. If the while condition is true, the loop goes around once and tests the while condition again. If the tested condition never changes inside the loop, the loop will keep looping indefinitely. The following statements cause a while loop to display the same line of text several times:

int limit = 5;
int count = 1;
while (count < limit) {
 System.out.println("Pork is not a verb");
 count++;
}


A while loop uses one or more variables that are set up before the loop statement. In this example, two integer variables are created: limit, which has a value of 5, and count, which has a value of 1. The while loop displays the text Pork is not a verb four times. If you gave the count variable an initial value of 6 instead of 1, the text would never be displayed.

      
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