CMPU4021-数学代写
时间:2022-11-22
CMPU4021 Distributed Systems
Assignment
Publishing date: 27th October 2022
Due Date: 24th of November 2022, 11:30am

This assignment represents the practical assessment for this subject, 30% of the overall
mark.

For this assignment you are required to design and implement a distributed application
that is a simulator of an electronic auction system.

There will be multiple clients and a server. The server will offer items for sale. The
client module will allow the user to bid for items. An item is sold to the highest bidder.
Your code will enable users only to bid for items – it will not conduct actual purchase
transactions.

Deliverables: Source code, Design Document, Demo

Client Requirements
- The clients should be able to use the all services offered by the auction server.

Clients should:
- Connects to the server. The item currently being offered for sale and the current bid or a
(or reserve price) are displayed.
- Enter the bid. The amount entered should be greater than the current highest bid.
- After a new bid is placed, the amount of the new bid must be displayed on the client’s
window/console.

Server Requirements
The server should offer the following services:
- Join auction
- Leave auction
- Bid on an item.
- List auction items

The server should:
- Receive connections from multiple clients, i.e. support concurrent multiple clients’
connections.
- After a client connects, notify the client which item is currently on sale and the
highest bid (or reserve price).
- Specify the bid period. Max allowed is 45 seconds. When a new bid is raised, the
bid period is reset back.
- When a new bid is placed, all clients are notified immediately. Clients should be
notified about the time left for bidding (when appropriate).
- If the bid period elapses without a new bid, then the auction for this item closes.
The successful bidder (if any) is chosen and all clients are notified.
- When an auction for one item finishes, another item auctioning should start.
Minimum of 5 items should be auctioned, one after another.
- Any item not sold should be auctioned again (automatically).

Extra functionalities
The server should also be able to:
- Allow including new items for sale in the auction server while the auction is
running.
- Register clients: unique name will suffice.


Implementation
The assignment must be implemented using Java sockets. Java multithreading, locks and
monitors should be used where necessary. Basic Java JDK should be used. It should work
with Java versions 8, 11 or 18 (as installed in Labs). No additional libraries/packages
should be used. If data storage is necessary, files should be used.

Submission
You must provide a design document which describes:
 your application architecture,
 setup
 detailed instructions how to run it.

The document should not exceed 3 pages, and must also include the following:
- Your name and student number.
- The subject title, i.e. Distributed Systems
- The assignment title i.e. Assignment
- The date, i.e. 24th of November 2022
- The following declaration: "I declare that this work, which is submitted as
part of my coursework, is entirely my own, except where clearly and
explicitly stated."






What should you submit?
1. The design document. It MUST be submitted as ONE word/pdf document.
2. Code (.java, .class, .bat files and any other files).
3. Put all the code and the design document in a directory named YOURNAME (i.e.
John Smith), ZIP it and upload it in Brightspace by 11:30am, 24th of
November 2022.


Your code must include setup and run instructions and the server.bat and client.bat
batch files. They will specify (contain) the command line for starting the server and
clients respectively. All code must be pre-compiled and ready to run, when
server.bat and client.bat are executed.


Example of the server.bat file:

rem Usage: java AuctionServer port
java -classpath . AuctionServer 1234

Example of the client.bat file:

rem Usage: java AuctionClient host port name
java -classpath . AuctionClient localhost 1234 john

Note1: ‘rem’ – comments;

Assessment Criteria

The application must be demo-ed in the labs. The demos will be scheduled.

Failure to provide code, documentation or demo will result in a mark of 0%.
You will be penalised an absolute value of 10% for every day that your assignment is
late.

Marking Scheme
- Requirements implementation (50%)
- Extra functionalities implementation (10%)
- General coding (error handling, comments) (13%)
- Design document (7%)
- Quality of the outcome (10%)
- Setup/Run/Demo (10%)


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