CS 231 Lab 9: Design and Implementation Project<

Design and Implementation Project (Writing Centered)

Assigned: Wed 19 April 2000

1st part due: Wed 26 Apr 2000
2nd part due: Fri 5 May 2000

Overview of the assignment

The basic purpose of this assignment is to give you some experience in designing a set of objects with fewer constraints and guidance than in recent labs and lecture examples. It will also serve as the main component of the English-language writing-centered work that you will include in your portfolio for the class. The first phase of the assignment (this week) will be just written work on the design; in the second phase, you will actually implement this design as a set of Java classes with variables and methods.

In the sections below I will describe the basic requirements for the project and give some ideas about how you should approach the design. I have already handed out in lecture a sample of the sort of format you should use for your design document (see me if you did not get a copy of this).

Basic structure of the assignment

As mentioned above, the assignment breaks down into two parts:

in the first, you will write out a medium-length design document in which you describe a Java programming project at a medium level of detail, including the overall structure of classes and methods you will use in an implementation. This part of the project emphasizes technical writing in English about the design, but should also include some diagrams or drawings.
In the second part, you will actually implement your project as a set of Java classes and methods, based of course on the design you write up in the first part. It is not expected that the final code will follow the design exactly since, of course, the design is only a sketch. You should, nevertheless, do everything you can to anticipate problems and issues that will come up in the implementation while you are working on the design document. This will give you the best opportunity to revise your goals before you actually begin programming.

The design part of the project should be completed before the programming part is done. You are responsible for having your design reviewd ("demo style", in lab) before you begin the programming work. You will want to keep a copy of the design document to place in your portfolio. Ideally, you should not "retro-fit" the design to match the implementation, but rather just leave it in its original form; you may want to include a retrospective paragraph or two along with your implementation code for the second half of the project in order to comment on those things that came up during coding which you did not anticipate.

Regarding content, i.e., the actual things that your project does on-screen, I am purposely giving you complete freedom to choose your own problem area and specific concept. Given the style of programming we have been using this semester, I expect many of youw ill want to do something graphical, although this is not at all required. You may, if you wish, choose to implement an extension or modification of the animation project you did for Lab 8, although there should be some significant changes in this case.

Form and content of the design document

In general, your design document should follow the form of the sample passed out in lecture, including:

a cover page including title, author, class number, etc.;
a contents page listing all sections and sub-sections;
an introductory section describing the project as a whole;
one section per class to be implemented, including a sub-section describing variables needed and one sub-section per method;
any appendices or other material which would be convenient to collect at the end (e.g., diagrams, especially if you have trouble including them in the body of the document for some reason).

More psecifically, the content of these sections ashould be as follows:

for the list of the classes, their names;
for each class you will implement, its name and a list of the variables you think they will need, along with their types (e.g., int, array, etc.);
for each class, a list of the methods that it will provide, including a return type (possibly void) and the names and types of any parameters;
for each method, a short English description of its structure (just a basic sketch will do);
a short English sketch of what a main driver method might look like;
a list of error conditions which might arise and how you intend to deal with them.

note that you will probably want to convert some of this material into comments for your Java program in the next stage of your work: you should keep this in mind when chooosing a word processor for the creating the report, so that you can easily cut-and-paste the text and re-use it in Java files.

Requirements for the implementation

Regarding the actual code for your project, you should have between 3 and 4 classes total, including one which will serve as the driver or applet class. You should also have a total of at least a dozen methods.

These are rather arbitrary limits, so you may break the letter of these rules so long as you can justify your choices and still demonstrate that your code has sufficient substance and depth.