Flow Control - SCJP Sun Certified Programmer for Java Platform SE6 - page 214

Here is the sequence of events for this while loop:
1. count is 1 and sum is 0, so the first time through the loop sum is 0 + 1 = 1 and count
gets incremented to 2.
2. Line 8 is false , the body of the loop is complete, and control jumps back up to the
boolean expression on line 6.
3. The loop executes again, sum is now 1 + 2 = 3, and count is now 3, so the loop executes
again.
4. sum is 3 + 3 = 6, count is 4, and the loop executes again.
5. sum is 6 + 4 = 10, count is 5, and the loop executes again.
6. sum is 10 + 5 = 15, count is 6, and line 8 is finally true .
7. Line 9 executes, causing myloop to terminate and control jumps to line 12.
Therefore, the output of this code is
sum = 15
count = 6
Using Labels
Note that the myloop label is not required in the previous example, but you can still use
a label even when it is unnecessary. You might use a label for clarifi cation if a loop is
long and it is unclear what is being affected by a break statement. You might also use
a label to ensure that modifi cations to the code later do not affect your use of the break
statement.
There are also situations where a label is required, as we will see in the next example.
The myloop label is not needed in the previous example, but there are situations where a
label is necessary (especially in nested loops) to obtain the desired behavior of a break. To
demonstrate this type of situation, let's start with a nested loop that does not use labels. See
if you can determine the behavior of the following loops:
15. int x = 1;
16. while(x <= 10) {
17. System.out.print(x++ + “ “);
18. for(int y = 10; y >= 1; y--) {
19. System.out.print(y + “ “);
20. if(y == 8)
21. break;
22. }
23. }