Lab 09

Bunch of Lines

Objective:

Write a bunch of classes that will draw a bunch of lines!  Don’t worry you don’t have to write any graphics, as that part is provided in the driver.  Each line is drawn based on a math function that takes in a given x coordinate and will return its y coordinate.

Lab Solution

• Functionality. (80pts)
• No Syntax Errors. (80pts*)
• *Code that cannot be compiled due to syntax errors is nonfunctional code and will receive no points for this entire section.
• Set-Up the Project (5pts)
• First download the driver and put it in your project
• Do not alter the provided code.
• Write an interface called Line
• Method definition
• getYPoint: This takes in a decimal value and returns a decimal value depending on the type of line.
• Write a class called SlopedLine
• This should implement Line
• Instance variable
• slope: a decimal value corresponding to the line’s slope
• Constructors
• Default
• Parameterized
• Accessors and Mutators for each variable
• Method
• getYPoint: this method takes in a decimal value corresponding to a x-coordinate and returns the y-coordinate based on the slope equation (y = slope*x)
• All must apply for full credit.
• Write a class called ExponentialLine
• This should implement Line
• Instance variable
• exponent: a decimal value corresponding to the line’s exponent
• Constructors
• Default
• Parameterized
• Accessors and Mutators for each variable
• Methods
• getYPoint: this method takes in a decimal value corresponding to a x-coordinate and returns the y-coordinate based on the slope equation (y = x^exponent)
• Write a class called SineLine
• This should implement Line
• Instance variables
• amplitude: a decimal value corresponding to the line’s amplitude
• frequency: a decimal value corresponding to the line’s frequency
• Create the following Constructors
• Default
• Parameterized
• Accessors and Mutators for each variable
• Methods
• getYPoint – this method takes in a decimal value corresponding to a x-coordinate and returns the y-coordinate based on a sine wave equation (y = amplitude*sin(x*frequency))
• Write a class called SawLine
• This should implement Line
• Instance variable
• modValue: a decimal value corresponding to the modulo peak of the wave
• Constructors
• Default
• Parameterized
• Accessors and Mutators for each variable
• Methods
• getYPoint – this method takes in a decimal value corresponding to a x-coordinate and returns the y-coordinate based on the equation (y = x mod modValue)
• Write a class called StaircaseLine
• This should implement Line
• Instance variables
• width: a decimal value corresponding to the stair’s width
• height: a decimal value corresponding to the stair’s height
• Constructors
• Default
• Parameterized
• Accessors and Mutators for each variable
• Methods
• getYPoint – this method takes in a decimal value corresponding to a x-coordinate and returns the y-coordinate based the width and height. HINT(using integer division and multiplying that by the height will achieve the effect).

HINT: If the lines look weird it may be a good idea to print out each of the coordinates and observing what is going on in the method getYPoint.

Example Dialog:

Lab Report Questions

1. Draw a UML class diagram for this project
2. Describe polymorphism

Solution Tests:

1. Is your name written as a comment in all source files?
2. Does the solution compile (no syntax errors)?

3. Does your output match the example GUI?

Lab Report

1. Create a section named “Problem” and describe this lab’s problem in your own words. (10pts).
2. Create a section named “Solution Description” and describe how the code solves the problem in your own words. (10pts).
3. Create a section named “Problems Encountered” and describe the various syntax, run-time, and logic errors that were encountered while implementing the solution. (10pts).
4. Describe polymorphism in OOP. (10pts).
5. Briefly describe the similarities between classes and interfaces in Java. (10pts).
6. Briefly describe the differences between classes and interfaces in Java. (10pts).
7. If we consider Classes to be “blueprints” for Objects, then what is the relationship between Interfaces and Classes? Interfaces and Objects? (10pts).
8. Is it possible to construct instances of an Interface in Java? (10pts).
9. What reserved word is used to establish a polymorphic relationship between a class and an interface in Java? (10pts).
10. What reserved word is used to establish inheritance (“is a”) relationship between two interfaces in Java? (10pts).

Finally:

• Upload the source code (.JAVA File Extension) to LabSolution09
• And written lab report (DOC, .DOCX, or .PDF file extension) to LabReport09
• To Blackboard
• Following these instructions.
• If there are problems, then let the instructor know as soon as possible.