CS 5381 - Topics in Software Design

			      HOMEWORK 4
		 (File $Date: 2008/02/28 05:27:44 $)

Due: March 6, 2008

You may do this homework in a group of two.

In this homework you will write a small Java application that allows
one to query one's scores in a networked environment. For this you
will use the C2 architectural style (see below). The key requirements
of this application are:

R1. The application consists of two programs, a server program and a
    client program that communicate with each other through TCP/IP
    sockets.

R2. The server program stores information about students; for each
    student it stores the student's name, PIN, and scores.

R3. The client program interacts with the user and the server program
    to retrieve and display the scores of a student.

R4. The server program should send to the client program the scores of
    a student if and only if the client program supplies the correct
    PIN of the student.

R5. The server program should be able to serve multiple clients
    simultaneously.

(1) Use the C2 architectural style to define an architecture for the
    above application. Identify components, connectors, and the
    configuration. For each component, 

    - Define precisely the set of messages (requests and
      notifications) that it sends to and is willing to receive from
      its top and bottom ports, and
   
    - Describe its behavior briefly in terms of the messages that it
      sends and receives.

    For each connector,

    - Define precisely the set of messages that it routes and
      broadcasts, and

    - Describe its behavior briefly in terms of its message routing
      and broadcasting.

(2) Based on your architecture above, implement the application in
    Java. Organize your components and connectors into class
    hierarchies by identifying common interfaces and factoring out
    common code to (abstract) superclasses. In C2, each component is
    recommended to an internal architecture consisting of three
    elements: domain translator, dialog and constraints, and wrapper.
    Follow this guideline when you implement your components; however,
    not all components may need such an internal structure.

WHAT AND HOW TO TURN IN
   
   Submit your programs, test outputs, and any supporting documents
   through the Assignment Submission page found in the Homework
   section of the course website. The page will ask you to zip, jar,
   or tar your programs, and upload a single file. The zip (jar or
   tar) file should include only a single directory named
   YourFirstNameLastName which contains all your source code files and
   other support files needed to compile and run your program; DO NOT
   INCLUDE BYTECODE (.class) FILES OR HTML FILES.  You should submit
   your programs before the class time on the due date.
  
   No late submissions will be accepted unless arrangements have been
   made in advance or unless unusual circumstances warrant an
   exception.

GRADING

   Clarity is important; if your writing or code is sloppy or hard to
   read, you will lose points.