Graphics and Inheritance

Objectives

  1. Analyze diagrams, documentation, and code to create functioning classes.

  2. Create an interesting class that will draw pictures using a gui.

  3. Start using keywords that are specific to inheritance.

Warning
 Be careful, this assignment may take extra time!
Description

Write a program that reads a list of graphics primitives from a text file and draws them in a window. This assignment creates a set of Java classes in a very primitive hierarchy to model the various graphics primitives: text, squares, rectangles, triangles, and circles, and ovals. Each primitive has a different set of attributes, for example text has font name, style, and size, and a rectangle has color, width, and height, etc. When your program is complete, you will be able to see the contents of the text file rendered inside of a window. In the next assignment you will substitute a more complex hierarchy of classes that takes advantage of inheritance to reduce duplication and force consistent behavior among graphics primitives. You will also another primitives, polygon.

Getting Started

  1. Create a project called P2.

  2. Download and import P2-starter.jar.
    After the import is complete, your P2 directory should look like this:

P2/
├── resources
│   ├── circles.txt
│   ├── ovals.txt
│   ├── rectangles.txt
│   ├── simplePrimitives.txt
│   ├── squares.txt
│   ├── text.txt
│   └── triangles.txt
└── src
    ├── DrawInterface.java
    ├── DrawProgram.java
    ├── Primitive.java
    └── UserInterface.java

Each test file has primitives for one type except for the simplePrimitives file which has 37 primitives for all different types.

Tip
 Do not be concerned that the Primitive class is empty. You will be adding code to the Primitive class in next assignment.
Data Description

Refer to the simplePrimitives file to see the format of the text files.

  • The color attributes in the file are numbers in the format RRGGBB, specified in hexadecimal, where each channel has eight bits.

    • For example FF0000 is red, 00FF00 is green, and 0000FF is blue, all maximum intensity.

  • The font name can either be "Times Roman" or "Arial".

  • All coordinates are integer values representing pixels on the drawing surface.

Coordinates

Java AWT(the underlying graphics library used in this project) uses a screen coordinate system where (0,0) corresponds to the pixel in the top left corner of the window. X increases towards the right and Y increases towards the bottom.

For specifications on the precise drawing location of the methods provided in UserIterface, consult the Java AWT Graphics class Javadoc.

Add New Classes

Create the following classes:

  • Square

  • Rectangle

  • Triangle

  • Circle

  • Oval

  • Text

Each shape should inherit from the Primitive class. For example:

public Square extends Primitive {
Implement the Shape Classes

Each shape requires certain fields and methods. This includes location, size, color, etc. You will need to figure out what each class should include through analyzing the following sources:

  • The code in the DrawProgram and UserInterface classes.

    • The code in the DrawProgram class is not complete, this will be the next part of your assignment. However, you should able to deduce what each shape needs from the code that is already provided.

  • The UML diagram below

  • The javadoc

Note
 Not all parameters are explicit in the UML diagram, so make sure that you look at the javadoc, as well.
UML
Complete the code in the DrawProgram class

The main method calls load, passing args[0] as the name of the text file containing graphics primitives, then it calls draw to draw the primitives. Try running the program with the files corresponding to the Text, Square, or Rectangle classes.

Once you have successfully tested these classes, complete the code for the following methods:

public ArrayList<Primitive> load(String filename);

public void draw(ArrayList<Primitive> primitives);
Sample Output

The image below shows the output from the simplePrimitives file:

SampleOutput
Specifications

Your program must meet the following specifications:

  • Work on your own, as always.

  • You must package all source files into P2.jar for submission.

  • Assignments should be implemented using Java 1.8.

  • Make sure your code runs on machines in the COMCS120 lab.

  • Submit your program to the Checkin.

  • Read the syllabus for the late policy.

  • We will be checking programs for plagiarism, so please don’t copy from anyone else.

Grading Criteria

  • 100 points for perfect submission.

  • 0 points for no submission, will not compile, submitted class file, etc.

  • Preliminary Tests:

    • compileTest: checks that all source files compile. (0 points)

    • testText: verifies the Text class with DrawProgram. (15 points)

    • testSquare: verifies the Square class with DrawProgram. (15 points)

    • testTriangle: verifies the Triangle class with DrawProgram. (20 points)

  • Final Tests:

    • testRectangle: verifies the Rectangle class with DrawProgram. (10 points)

    • testCircle: verifies the Circle class with DrawProgram. (10 points)

    • testOval: verifies the Oval class with DrawProgram. (10 points)

    • testSimple: verifies the drawing of simplePrimitives file. (20 points)

Important
 Submit P2.jar to Checkin