Description
1. Objective
The objective of this programming assignment is to implement the dining
philosopher’s problem using a monitor for synchronization.
2. Source Code
There are five files that come with the assignment. A soft copy of the code is
available to download from the course web site. This time the source code is barely
implemented (though compiles and runs). You are to complete its implementation.
2.1 File Checklist
Files distributed with the assignment requirements:
common/BaseThread.java – unchanged
DiningPhilosophers.java – the main()
Philosopher.java – extends from BaseThread
Monitor.java – the monitor for the system
Makefile – take a look
3. Background
This assignment is a slight extension of the classical problem of synchronization –
the Dining Philosophers problem. You are going to solve it using the Monitor
synchronization construct built on top of Java’s synchronization primitives. The
extension refers to the fact that sometimes philosophers would like to talk, but only one
(any) philosopher can be talking at a time while they are not eating. If you need help,
consult the references at the bottom.
4. Tasks
Make sure you put comments for every task that involves coding to the changes
that you’ve made. This will be considered in the grading process.
Task 1: The Philosopher Class
Complete the implementation of the Philosopher class, that is all its methods
according to the comments in the code. Specifically, eat(), think(), talk(), and run()
methods have to be implemented entirely. Non-mandatory hints are provided within the
code.
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Task 2: The Monitor
Implement the Monitor class for the problem. Make sure it is correct, deadlockfree and starvation-free implementation that uses Java’s synchronization primitives, such
as wait() and notifyAll(); no use of Semaphore objects is allowed. Implement the four
methods of the Monitor class; specifically, pickUp(), putDown(), requestTalk(), and
endTalk(). Add as many member variables and methods to monitor the conditions
outlined below as needed:
1. A philosopher is allowed to pickup the chopsticks if they are both available. That
implies having states of each philosopher as presented in your book. You might want to
consider the order in which to pick the chopsticks up.
2. If a given philosopher has decided to make a statement, they can only do so if no one
else is talking at the moment. The philosopher wishing to make the statement has to wait
in that case.
Task 3: Variable Number of Philosophers
Make the application to accept a positive integer number from the command line,
and spawn exactly that number of philosophers instead of the default one. If there are no
command line arguments, the given default should be used. If the argument is not a
positive integer, report this fact to the user, print the usage information as in the example
below:
% java DiningPhilosophers -7.a
“-7.a” is not a positive decimal integer
Usage: java DiningPhilosophers [NUMBER_OF_PHILOSOPHERS]
%
Use Integer.parseInt() method to extract an int value from a character string. Test your
implementation with a variable number of philosophers. Submit your output from “make
regression”.
5 Deliverables
Submit the complete source code after the last task you managed to complete as
well as the final output you are getting. Archive it into say pa3.zip and submit it
electronically.
Operating systems Programming assignment 3 comp346
Computer science and software engineering Page 3
6 Grading Scheme
Grading Scheme:
===============
T# MX MK
————————-
1 /2
2 /6
3 /2
————————-
Total: /10
(T# – task number, MX – max (out of), MK – your mark)
7 References
1. Java API: http://java.sun.com/j2se/1.3/docs/api/
2. http://java.sun.com/docs/books/tutorial/essential/TOC.html#threads
