Exiting a Loop

The normal way to exit a loop is for the condition that is tested to become false. This is true of all three types of loops in Java: for, while, and do-while. However, there might be times when you want a loop to end immediately, even if the condition being tested is still true. You can do this with a break statement, as shown in the following code:

int index = 0;
while (index <= 1000) {
 index = index + 5;
 if (index == 400)
 break;
 System.out.println("The index is " + index);
}


The condition tested in the while loop sets it up to loop until the value of the index variable is greater than 1,000. However, a special case causes the loop to end earlier than that: If index equals 400, the break statement is executed, ending the loop immediately. Another special-circumstance statement you can use inside a loop is continue. The continue statement causes the loop to exit its current trip through the loop and start over at the first statement of the loop. Consider the following loop:

int index = 0;
while (index <= 1000) {
 index = index + 5;
 if (index == 400)
 continue;
 System.out.println("The index is " + index);
}


In this loop, the statements will be handled normally unless the value of index equals 400. In that case, the continue statement causes the loop to go back to the while statement instead of proceeding normally to the System.out.println() statement. Because of the continue statement, the loop will never display the following text:

The index is 400


You can use the break and continue statements with all three kinds of Java loop statements.

      
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