Question

Purpose: To write an Object-Oriented application using abstraction, inheritance, encapsulation, and polymorphism to handle an inheritance structure of various shapes.

Details:

Implement the following Shape hierarchy: a box around each shape name and arrows pointing to the shape from each (Circle, Square, Triangle)

Shape

Circle Square Triangle

  

Use the following as a guide:

• The Shape class should be abstract and contain two abstract methods:
  • getArea – Which calculates the area of the shape and returns that value as a double.
  • getPerimeter – Which calculates the perimeter of the shape and return that value as a double.

And one concrete method:

• • getName – that returns the shape’s name as a String.
• The Circle class’s constructor should take a single parameter of type double representing its diameter. No error checking is required.
• The Square class’s constructor should take a single parameter of type double representing the length of its sides. No error checking is required.
• The Triangle class’s constructor should take a single parameter of type double representing the length of its sides. No error checking is required.
• No set and get methods are needed. Do not include them in the any of the classes.

Create a second class called TestShapes that contains the main method. This test class does not need to ask users for input. The class should do the following:

1. Create an array of size three, that uses Shape references. Fill the array with one of each concrete class in the hierarchy.
2. Iterate through the array of shapes and doing the following:
   1. Display the shape’s name.
   2. Display the shape’s area.
   3. Display the shape’s perimeter.

*******Ensure that your program is properly formatted and it follows all Java naming conventions.

Answer 1

Thanks for the question.

Below is the code you will be needing Let me know if you have any doubts or if you need anything to change.

Also, designed the UML diagram.

If you are satisfied with the solution, please rate the answer. Thanks

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public abstract class Shape {


    public abstract double getArea();

    public abstract double getPerimeter();

    public String getName() {
        return "Abtract Shape";
    }

}

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public class Circle extends Shape {

    private double diameter;

    public Circle(double diameter) {
        this.diameter = diameter;
    }

    @Override
    public double getArea() {
        return Math.PI * (diameter * diameter) / 4;
    }

    @Override
    public double getPerimeter() {
        return Math.PI * diameter;
    }

    @Override
    public String getName() {
        return "Circle";
    }


}

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public class Square extends Shape {

    private double length;

    public Square(double length) {
        this.length = length;
    }

    @Override
    public double getArea() {
        return length * length;
    }

    @Override
    public double getPerimeter() {
        return 4 * length;
    }

    @Override
    public String getName() {
        return "Square";
    }
}

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public class Triangle extends Shape {

    private double side1;
    private double side2;
    private double side3;

    public Triangle(double side1, double side2, double side3) {
        this.side1 = side1;
        this.side2 = side2;
        this.side3 = side3;
    }

    @Override
    public double getArea() {

        double s = (getPerimeter()) / 2;
        return Math.sqrt(s * (s - side1) * (s - side2) * (s - side3));

    }


    @Override
    public double getPerimeter() {
        return side1 + side2 + side3;
    }

    @Override
    public String getName() {
        return "Triangle";
    }
}

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public class TestShapes {


    public static void main(String[] args) {

        //Create an array of size three, that uses Shape references
        Shape shapes[] = new Shape[3];

        shapes[0] = new Circle(7.0);
        shapes[1] = new Square(5.5);
        shapes[2] = new Triangle(5, 6, 7);

        //Iterate through the array of shapes and doing the following:
        for (int i = 0; i < shapes.length; i++) {
            System.out.println("Shapes Name: " + shapes[i].getName());
            System.out.println("Shapes Area: " + shapes[i].getArea());
            System.out.println("Shapes Perimeter: " + shapes[i].getPerimeter());
            System.out.println();
        }
    }
}

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