In an office environment, there are an unspecified number of desks, and two kinds of workers: clerks and cleaners.
Workers behave as follows:
Clerks may arrive at the office at any time. In order to get to work, they wait until they have exclusive access to an available desk that has been cleaned. After working for an unspecified amount of time, they leave the desk, which needs cleaning.
Cleaners work on one desk at a time. Each cleaner waits until a clerk leaves a desk, at which point the cleaner starts cleaning the desk, and then signals when cleaning is completed.
We model the office environment in Java pseudo-code using monitor classes:
• Desks corresponds to instances of a class Desk, whose details are irrelevant but has a binary state is_clean. • The office is an instance of type Office with interface:
• Clerks and cleaners correspond to threads sharing an instance of Office and calling its public methods continuously as follows:
The goal of this exercise is to provide a monitor class OpenOffice with interface Office, whose behavior
follows the above description. Use thread sleep function to simulate task durations, assume ‘work at
desk’ task takes 510 seconds and ‘clean desk’ task takes 15 seconds.
Develop the above monitor class OpenOffice and demonstrate it using a unit test console application.
Assume the office has 100 desks, 20 cleaners and 120 clerks.
There is competition among clerks and cleaners, as well as coordination between clerks and cleaners.