COMPSCI 230 The Bouncing Program Solution

In this programming assignment, you are asked to add extra functions to a skeleton bouncing program that is provided to you. The aim of the assignment is to give you experience with object-oriented programming, principles of inheritance and polymorphism.
This assignment is marked out of 60 marks, with 50 marks being the equivalent of “full marks” for this assignment. Any excess marks may be used to compensate for loss of marks in other assignments or Coderunner.

Introduction - The Bouncing Program
The application, as given, is a simple bouncing program designed to let different shapes move around along various paths. Most of the code is already provided for you, but you will need to add more shapes. The program is easy to use: The only user actions are to create shapes based on the classes you will write, and to select
individual existing shapes on the panel and change their properties.
Actions
Shape Creation:
The user can create a new shape by clicking anywhere within the panel area of the program. The properties of the newly created shape are based on the current values saved in the appropriate UI fields (e.g. height, width border colour, fill colour and path). Once created, the shape will start moving.
Selecting/deselecting shapes:
A user can select a shape by clicking anywhere on the shape. A selected shape shows all its handles. The user can change the path types/widths/heights/border
colours/fill colours for all selected shapes by changing the current values with the help of the tools provided at the top of the application interface. (Note: The shape
type itself cannot be modified once a shape has been created.) Clicking on a selected shape will deselect it.
Tools
Shape Combo
Box:
The ‘Shape’ combo box lets you select the shape type for the new shapes that get created when you click on the panel area. In the skeleton application, the combo box is pre-populated with icons for the shape classes you will create. Clicking in the panel area to create a shape as described above will then create a shape of the selected type.
Path Combo
Box:
Users may select one of several moving paths for shapes from the ‘Path’ combo box.
Selecting a new path changes the path of all currently selected shapes. The newly selected path also becomes the current path for any new shapes that the user creates. In the skeleton program, two paths are available: a “falling path” that sees shapes move from the top of the panel to the bottom with a little bit of back-and-forth sideways movement, and a “bouncing path” that lets the shape bounce off whichever boundary it hits.
Width
TextField:
Users may change the current width of new shapes and currently selected shapes by entering a valid number in the width text field and pressing “ENTER”.
Height
TextField:
Users may change the current height of new shapes and currently selected shapes by entering a valid number in the height text field and pressing “ENTER”.
COMPSCI 230
Assignment ONE
Computer
Science
Set the current
shape type Set the current
path type
Set the current
height & width
Set the
Animation speed
Set the current
border & fill colour
COMPSCI 230 S1 - Assignment 01
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Border Button Users may change the current border colour of new shapes and currently selected shapes by pressing the border button.
Fill Button Users may change the current fill colour of new shapes and currently selected shapes by pressing the fill button.
Start Button: Starts the animation.
Stop Button: Stops the animation.
Animation
Slider:
Users may use the animation delay slider to adjust the speed of the animation. Popup Menu: The application has a popup menu, which is activated by clicking the right mouse button anywhere in the panel area (on a windows machine). The popup menu contains a menu item called “Clear All” which allows the user to clear all shapes from the program.
What you are to do
Firstly, become familiar with the program supplied. The files included in the program are as follows:
 A1.java
 AnimationPanel.java
 MovingShape.java
 MovingOval.java
Download all source files from the assignment course page. You are required to modify the program and add a
few more shapes into the program. Your assignment is divided into several stages for ease of completion. Please
complete the assignment in order of the stages.
In order to complete the assignment, you will need to create additional classes and make changes to
AnimationPanel.java, MovingShape.java and A1.java. You need to be familiar in particular with the
purpose of two methods in MovingShape.java, which you may wish to override in the new shape subclasses
you will create:
 draw(): This method actually draws the shape in question, using an object that is a subclass of the
abstract Graphics2D class, which is part of the Java AWT graphics package and extends the
Graphics class in that package. You will need to override this method in every shape subclass you
create, and ensure that the respective shape gets drawn properly. You should find the API
documentation of the Graphics2D class useful:
https://docs.oracle.com/javase/10/docs/api/java/awt/Graphics2D.html
 contains(): This method takes a Point parameter and is meant to return true if the Point is
inside the shape and false if it is not. Since you will be creating different shapes, you will need to
override this method for each shape that has a new outline, unless it makes sense to simply inherit it
from an ancestor class with the same outline.
Once you have created a new shape subclass, you will need to add it to AnimationPanel. The
createNewShape() method in AnimationPanel.java is the place to do this.
You must include your name, UPI and a comment at the beginning of each file you create or modify.
Stage 1: The MovingRectangle Class (5 marks)
You are required to add a MovingRectangle subclass to your program. This class should draw a
rectangle/square based on the mouse-point, the current width, the current height, the current border and fill
colours and, the current moving path saved in the AnimationPanel. Some examples are shown as below:
Assessment criteria:
 [1 mark] The class hierarchy should be developed sensibly and in accordance with good object-oriented
programming practice.
 [1 mark] The draw method is overridden correctly
 [1 mark] The contains method is overridden correctly
 [1 mark] Users should be able to create a new rectangle using the current properties in the program.
COMPSCI 230 S1 - Assignment 01
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 [1 mark] Users should be able to change the fill colour, border colour, width, height and bouncing path
of selected rectangles.
Stage 2: The MovingSquare Class (5 marks)
You are required to add a MovingSquare subclass to your program. This class should draw a square based on
the mouse-point, the size (i.e. the smallest dimensions from the current width and the current height), the current
border colour, the current fill colour, and the current moving path saved in the AnimationPanel.
Assessment criteria:
 [3 marks] The class hierarchy should be developed sensibly and in accordance with good
object-oriented programming practice. (Do you need to override the draw & contains method in the
MovingSquare class? Do you need to override any existing methods?)
 [1 mark] Users should be able to create a new square using the current properties in the program.
 [1 mark] Users should be able to change the fill colour, border colour, size and bouncing path of
selected squares.
Stage 3: The MovingQuadPie Class (10 marks)
You are required to add a MovingQuadPie subclass to your program. This class should draw a special shape
based on the mouse-point, the size (i.e. the smallest dimensions from the current width and the current height),
the current border colour (e.g. orange), the current fill colour (e.g. blue), and the current moving path saved in
the AnimationPanel. Some examples are shown as below.

Assessment criteria:
 [3 marks] The class hierarchy should be developed sensibly and in accordance with good
object-oriented programming practice. Do you need to override the draw and/or contains?
 [4 marks] Users should be able to create a special shape using the current properties in the program.
 [3 marks] Users should be able to change the fill colour, border colour, size and bouncing path of
selected shapes.
Stage 4: The MovingSquarePattern Class (10 marks)
You are required to add a MovingSquarePattern subclass to your program. This class should draw a special
pattern based on the mouse-point, the size (i.e. the smallest dimensions from the current width and the current
height), the current FILL colour (e.g. black), and the current moving path saved in the AnimationPanel. Some
examples are shown as below:

Assessment criteria:
 [3 marks] The class hierarchy should be developed sensibly and in accordance with good
object-oriented programming practice. Do you need to override the draw and/or contains?
 [4 marks] Users should be able to create a new shape pattern using the current FILL colour, size and
path in the program.
COMPSCI 230 S1 - Assignment 01
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 [3 marks] Users should be able to change the FILL colour, size and bouncing path of selected patterns.
Stage 5: Adding a New Path (10 marks)
In this part, you are required to add your own designed path to the bouncing program. The MovingPath is an
abstract inner class which contains an abstract method. You are required to add a new subclass which extends
the MovingPath and implement the move() method.

Assessment criteria
 [2 marks] The class hierarchy should be developed sensibly and in accordance with good
object-oriented programming practice.
 [3 marks] Users should be able to add a new shape that moves in your own designed path.
 [2 marks] Users should be able to change the bouncing path of selected shapes to your own designed
path.
 [3 marks] In the marker’s opinion, your work shows great preparation, creativity or effort.
Stage 6: Using an ArrayList (10 marks)
The maximum number of shapes that can be stored in your program is 10 at this stage. However, you are
required to modify the AnimationPanel class which enable users to store more than 10 shapes using an
ArrayList. Replace the array in AnimationPanel class with an ArrayList. You will need to modify 10
different methods in AnimationPanel: mouseClicked, createNewShape, setCurrentPathType,
setCurrentWidth, setCurrentHeight, setCurrentBorderColor, setCurrentFillColor,
resetMarginSize, clearAllShapes, and, paintComponent.
Assessment criteria
 [2 marks] Shapes are stored in an ArrayList.
 [3 marks] Users should be able to create a new shape and add it to the ArrayList.
 [2 marks] Users should be able to remove all shapes from the ArrayList
 [3 marks] Users should be able to modify the fill and border colours, path, height, width and margin
sizes of selected shapes in the ArrayList.
Bonus (10 marks)
You are now required to get creative and add your own special shape(s) that will make the bouncing program
more interesting! You may want to add Text, Images, 3D shapes, Sound etc into the bouncing program.