CS102- Algorithms and Programming II Lab 03 Solved

CS102- Algorithms and Programming II
Lab 03
Lab Objectives: Inheritance, Abstract Classes, Polymorphism

Notes:

●      For all labs in CS 102, your solutions must conform to these CS101/102 style guidelines.

●      Create a Java Project named Lab03. Put all of your classes in this project.

●      Remember to include javadoc comments for each class and method.

●      Upload your solution as a single .zip file to the Lab03 assignment by the end of your section’s lab session in the week of March 1. You must use the following naming convention: Lab03_Surname_FirstName.zip where Surname is your family name and FirstName is your first name. You may upload multiple times; the last upload will be considered.

Create an abstract class called Shape2D. A 2D shape has two properties: x and y coordinates of its center. Its constructor takes two parameters: x and y coordinates. You may assume that  both coordinates are integers.

This class has the following methods:

●      public abstract double calculatePerimeter() - returns perimeter of a

2D shape. This method will be an abstract method.

●      public abstract double calculateArea() - returns area of a 2D shape.

This method will be an abstract method.

●      public double calculateDistance( Object anyShape ) - returns the euclidean distance between the centers of two Shape2D objects. If anyShape parameter is not a Shape2D instance, it should return -1.

●      public String toString() - returns a string representation of two properties: x and y coordinates of its center. Make sure to use @Override annotation before the method definition, because this method overrides the toString() method in our superclass Object.

●      public boolean equals( Object o ) - returns true if given object is a

Shape2D object that is equal to this one; false otherwise. Make sure to use @Override annotation before the method definition, because this method overrides the equals() method in our superclass Object.

After creating the Shape2D class, create the following three classes.

●      Create a class Circle which extends Shape2D class. Circle class has an additional property, radius. Circle is a 2D shape, therefore its constructor takes three parameters, x and y coordinates and radius.

●      Create a class Rectangle which extends Shape2D class. Rectangle class has additional properties, height and width. Its constructor takes four parameters; x, y coordinates, height and width.

●      Create a class Square which extends Shape2D class. Square class has an additional property, sideLength. Its constructor takes three parameters, x and y coordinates and sideLength.

All classes will also implement calculatePerimeter() and calculateArea() methods, and override toString() and equals() methods. Reuse the toString() and equals() implementations in the super class when implementing these methods in the subclasses with @Override annotation before the method definitions.

Write a test class, ShapeTest. Create an array of three shape objects: one rectangle, one square and one circle. Then, find a 2D Shape object with the longest perimeter and the object with the largest area to the screen and print whether these objects are Square, Circle or Rectangle. You should do this by implementing and using the following methods.

●      public static Shape2D findLargestArea() - Write a method which takes an array of Shape2D objects as parameter and returns the shape with the largest area in the shape list.

●      public static Shape2D findLongestPerimeter() - Write a method which takes an array of Shape2D objects as a parameter and returns the shape with the longest perimeter in the shape list.

Demonstrate the uses of your toString() and equals() methods from these classes. Also, calculate the distances between these three Shape2D objects.

Sample Run