This assignment is due on Monday, March 13, by 7:00 p.m. in the box in CS 189.

Summary: Finally, we consider concurrency and exceptions.

Readings and review questions: You should know the answers to the review questions listed below, but you do not have to turn them in. Remember that going over all of the review questions we've singled out is good preparation for the final.

Chapter 12: 1-6, 19-24

Chapter 13: 1-4, 11-23

(a) This part refers to the Java code on pages 524 and 525, with these substitutions:

• Use new Queue(5) instead of new Queue(100) (in other words, just create a queue with 5 elements).



• In Producer's run method on page 525, change the loop to read:
  while (true) {
   if TimeToAct() {
     //-- Create a new_item
     buffer.deposit(new_item);
}}



• Change the loop in Consumer's run method to call TimeToAct the same way.

Assume that both threads start running at 7:00 a.m. Assume that consumer1 tries to consume a new item every 5 minutes, starting at 7:10 a.m., stopping at 7:36 a.m., and starting again at 9:25 a.m. These timings are handled (magically) by the function TimeToAct, which just returns false until the time for the next action comes up.

Assume that producer1 produces an item every 10 minutes from at 7:21 a.m. to 9:21 a.m. Each item is an integer representing the time (721, 731, 741, ..., 921).

(a.1) Give a snapshot of the concurrent processes' execution every 5 minutes, starting at 7:03 a.m. (7:03, 7:08, 7:13, 7:18, ...) and continuing until the contents don't change any more. Each snapshot should show the contents of buff1 and the state of execution of the threads producer1 and consumer1 (i.e., where in the code they are executing).

(a.2) (extra credit) Rewrite the producer/consumer code to use the sleep method instead of the TimeToAct function described above.

(a.3) (extra credit) Implement this producer/consumer problem in Java; turn in your code, a test plan, and the results. Make sure you can do part (e.1) by hand, though; you won't have a computer on the final exam.

(b) Briefly answer problems 6, 7, 8, and 15 in the problem set on page 564. For extra credit, do either problem 12 or 13.