CS 2102 Homework Assignment #5 [not ready yet]

Assigned: Monday November 27, 2006, 10:00 AM
Due: Tuesday December 5, 2006, 10:00 AM              *** new date: extra day on assignment ***

Guidelines:

Now available.

The context for this homework assignment is a small game, known by various names, including: Amidakuji (阿 弥 陀 籤) and Ghost Leg (畫 鬼 腳). For the purpose of this assignment, we will call the game Amida. The goal of this assignment is to produce a well-designed class that conforms to the behavioral interface provided by the professor. You will validate the correct functioning of your classes by means of JUnit test cases. In addition, I have provided a small GUI that can be used to play the Amida game once your working classes are complete.

Description

Read the Amida project description. To guide you in completing your solution, I have provided you with a set of existing Java classes and interfaces. The goal is to design a class (and supporting classes) that implements the provided amida.AmidaInterface. See the code example as found in Examples/amida in the SourceForge/Eclipse public area. In the following points, I break down the assignment of points for this assignment.

Initial Design

I believe you should adopt the following strategy.

• There can be any number of vertical lines on an Amida board. Thus you will need to maintain a linked list of LineNodes, each of which represents a vertical line.
• There can be any number of horizontal edges on an Amida board. Because each edge connects two vertical lines, it may not be clear how you should represent the information. I suggest that you consider each vertical line to have a number of horizontal edges emanating from it to the right. Thus, for the following Board:
  
  
  
  you should store the following information:
  
  
  that is, where there is a linked list containing five LineNode objects. Each of these LineNode objects is maintaining a linked list of EdgeNode objects. The first three lines (reading from left to right) each has a list of four EdgeNode objects, while the fourth vertical line has a list of three EdgeNode objects.

This project, then, is consumed by the idea of creating an AmidaBoard class to maintain these lists of information in the face of requests to:

• void addLine()
• boolean removeLine()
• void addEdge (int line, int verticalPos)
• boolean removeEdge (Edge edge)
• void removeAll()

Note that the vertical position starts at ZERO at the top of the vertical line, and increases as you move vertically down the line. This may seem counter-intuitive, but it is the standard for most computer graphics.

Once you are able to properly maintain this information, you can implement the following requests:

• int numLines()
• int numEdges (int line)
• Edge getEdge (int line, int num)

Only then should you even contemplate attacking the two final methods:

• boolean tooClose(int line, int verticalPos)
• int exitLine(int line)

Each of these methods is clearly defined within the amida.AmidaInterface interface description file that is now available to you, thus your AmidaBoard class must implement this interface. Your class must provide a meaningful default constructor that takes no arguments.

Where do you start?

Watch the HW5 skeleton video. Think about the requirements that you are expected to implement. I would suggest that you consider adding the following methods to LineNode:

• public boolean add (int verticalPos) throws AmidaException -- Add an edge to the neighboring line to the right
• public void removeAll() -- Remove all horizontal edges emanating from this line
• public boolean remove(int verticalPos) -- Remove the horizontal edge emanating from this line to the right at the given vertical position [if one exists]
• public boolean tooClose(int verticalPos) -- Would a new edge emanating from the right of this line be too close to an existing edge that already emanates to the right?
• public int numEdges() -- Return the number of edges in the linked list of edges for this line
• public Edge getEdge(int n) -- Return the n^th edge from the top (n >= 1) emanating from this line
• public EdgeNode getEdgeAfter(int verticalPos) -- Return the EdgeNode (or null if none exists) which appears next vertically

Regarding the AmidaBoard class, the interface defines all methods that you will need to provide. The exitLine(int line) method on AmidaBoard is going to be a challenge to write: Consider the following algorithm:

Point Allocation

1. [24 pts.] EdgeNode and LineNode implementation. 
    
2. [44 pts.] AmidaBoard implementation. Points allotted as found in the hw5-guidelines.
    
3. [32 pts.] There is only a single JUnit test class that I am looking for. Note that it is actually quite comprehensive. When testing, you should follow the basic principle that you must first test smaller things before you test larger things. This means that you should identify those methods (and constructors) that can be immediately be tested.

All classes must be fully documented, according to the JavaDoc standard introduced in class and used throughout all class examples.