In the programming assignments, you are going to develop a simple distributed ticket reservation system (DTRS). This system is used by customers (with unique 6-digit customerIDs) to reserve show tickets with different box offices and manage their reservations.
Assume that a show is identified by a unique showID (like MTL175 or TOR432) the first three characters of which identify the box office (like MTL for Montreal or TOR for Toronto) and the last three digits specify the show (like 175 or 432). The DTRS will run multiple servers, one per box office, maintaining the number of tickets available for each of the shows in that box office in main memory and the list of (customerID, numberOfTickets) for the already reserved tickets for each of the shows in that box office in a file (one file per show).
Customers may invoke the following operations on the box office servers through their client program:
reserve(customerID, showID, numberOfTickets): Reserve the required number of tickets (numberOfTickets) for the specified show (showID) for the customer (customerID).
cancel(customerID, showID, numberOfTickets): Cancel the specified number of tickets (numberOfTickets) for the show (showID) that the customer (customerID) had already reserved. The number of tickets cancelled may be smaller than or equal to the number of tickets reserved.
check(showID): Returns the number of tickets currently available for the specified show (showID).
Thus, this application has BoxOfficeServers (one per box office) implementing the above operations for the box offices and CustomerClients (one per customer, invoking the customer operations at the BoxOfficeServer managing the show on which the operation is to be done) on behalf of the customers as necessary. Thus, each BoxOfficeServer manages the shows within that box office and performs client operations on these shows; and a CustomerClient invokes a client operation at that BoxOfficeServer managing the show indicated in the operation. When a BoxOfficeServer is started, it registers its address and related/necessary information with a central repository. For each customer operation, the CustomerClient finds the required information about the BoxOfficeServer (based on the showID) from the central repository and invokes the corresponding operation.
Write the Java RMI interface definition for the BoxOfficeServer with the specified operations.
Implement the BoxOfficeServer.
Design and implement a CustomerClient which invokes the server to test the correct operation of the DTRS involving multiple BoxOfficeServers (each with a few shows) and multiple customerClients.
You should design a server that maximizes concurrency. In other words, use proper synchronization that allows multiple customers reserve/manage for the same or different shows at the same time.