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Triangle Project

Part 1:Triangle.java

Write the complete class definition for the Triangle class. The Triangle class consists of the following:

• side1, side2 and side3: represents the side lengths of a triangle and is expressed as an double.

Additionally,

• The Triangle class contains a default constructor, that initializes a generic triangle with all sides set to a value of 0 (zero).
• Three overloaded constructors for creating
1. Triangle objects with all sides as equal (equilateral) – provides measurement of one side only
2. Triangle objects with two sides as equal (isosceles) – provides measurement of two sides (where side1 represents the equal side and side2 represents the other side)
3. Triangle objects with all unequal sides (scalene) – provides measurement of all the sides
• Accessor method to access all the properties of the Triangle class
• Helper method (getTriangleType()) to get the type of the triangle object – returns equilateral/ isosceles/ scalene – as String. The method must return “generic” in case the triangle is created using the default constructor.

Part 2: TriangleRunner.java

Write the complete class definition for the runner class named TriangleRunner class, that makes use of the Triangle class. The main method of the TriangleRunner class should do the following:

• Use the generic constructor to initialize a triangle object (genTri).
• Use the three overloaded constructors to initialize three triangle objects (equiTri, isoTri, ScaTri).
• Use the helper method (getTriangleType())) to get and print the triangle type for each triangle object created above (genTri, equiTri, isoTri, ScaTri).

Solution:

Part 1:Triangle.java

Default Constructor

    public Triangle()
    {
        side1= 0.0;
        side2= 0.0;
        side3= 0.0;
    }

Three Overloaded Constructors

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

Helper Method

    public String getTriangleType()
    {
        if ((this.side1 == this.side2) && (this.side1 == this.side3))
        {
            if (side1==0)
                return "generic";
                else
                    return "equilateral";
        }
        else if ((this.side1 == this.side2) || (this.side2 == this.side3) || (this.side2 == this.side3))
        {
            return "isosceles";
        }
        else return "scalene";
    }

Part 2:TriangleRunner.java

Using Constructors

        Triangle genTri = new Triangle();
        Triangle equiTri = new Triangle(2.1);
        Triangle isoTri = new Triangle(2.1, 3.5);
        Triangle ScaTri = new Triangle(2.1, 3.5, 4.3);

Using Helper Method

        System.out.println("Triangle type for genTri object is: "+ genTri.getTriangleType());
        System.out.println("Triangle type for equiTri object is: "+ equiTri.getTriangleType());
        System.out.println("Triangle type for isoTri object is: "+ isoTri.getTriangleType());
        System.out.println("Triangle type for ScaTri object is: "+ ScaTri.getTriangleType());

Java project files (with Runner code):

• Triangle.java
• TriangleRunner.java

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