Exercise : jGRASP Debugger

We are going to practice using the jGRASP debugger with Hailstone.java. This program computes a sequence of integers called a hailstone sequence. (This is related to an unsolved problem in mathematics known as the Collatz Conjecture.)

• Recall: To Set a breakpoint, move your cursor to the beginning of the desired line until you see a stop-sign icon and click.
• Recall: To run a program in debug mode, click the debug icon (looks like a ladybug).
• Recall: To resume a stopped program, press the top-left play or step buttons.

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Exercise - Values of value

• For this exercise you will trace the first call: printHailstoneMaxMin(7, 10);
• Set a breakpoint that will allow you to determine the first several distinct values of the variable value as the loop executes.

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Exercise - Values of min

• Now you will trace the second call: printHailstoneMaxMin(7, 20);
• Clear your previous breakpoint by clicking on it a second time, then set a new breakpoint for the second method call, and resume execution.
• Use your new breakpoint to determine the first several distinct values of min during the second call.

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