The source line numbers given in this tutorial assume you have added the additional code given in Editing Source Code.
if (x + w > d.width) {
This line was chosen so that you can track the change in the values of variables as the program goes through the loop. In most cases, you will set a breakpoint in a line where you think a bug occurs in your program.
Java WorkShop runs the program until it reaches the breakpoint. The line containing the new breakpoint changes to green to indicate where program execution stopped. The Threads/Stack window is updated.
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