Chapter 8, Problem 4PP

Program Plan Intro

Displaying right triangle, rectangle, and square along with their areas and perimeters

Program Plan:

Filename: Test.java

• • Define main function.
  • ○ Create the objects for “RightTriangle”, “Rectangle”, and “Square” classes and pass the input value to the respective methods.
  • ○ Call the “drawHere” method with “RightTriangle” object “rt”.
  • ○ Call the “findArea” and “findCircumference” methods with “RightTriangle” object “rt”.
  • ○ Call the “drawHere”, and “drawAt” methods with “Rectangle” object “r”.
  • ○ Call the “findArea” and “findCircumference” methods with “Rectangle” object “r”.
  • ○ Call the “drawHere”, and “drawAt” methods with “Square” object “s”.
  • ○ Call the “findArea” and “findCircumference” methods with “Square” object “s”.
  • ○ Display the all the outputs.

Filename: RightTriangle.java

• • Define the “RightTriangle.java” class extends from “ShapeBase” class that implements “ShapeInterface”.
• • Declare the required variables.
• • Define the default constructor, and constructor for the class.
• • Define the “set” method.
  • ○ Set the value.
• • Define “drawHere” method.
  • ○ Call the “drawTop” method.
• • Define the “drawTop” method.
  • ○ Declare the variable “startOfLine” and assign the value of offset plus base divided by 2.
  • ○ Call the “skipSpaces()” method with “startOfLine” value.
  • ○ Display the “*” character.
  • ○ Declare the variable “lineCount” and assign the value of base divided by 2 minus 1.
  • ○ Declare the “insideWidth” with value 1.
  • ○ The “for” condition is used to display the “*” character in triangle shape.
    • ■ Decrement the “startOfLine” value.
    • ■ Call the “skipSpaces()” method with “startOfLine” value.
    • ■ Display the “*” character.
    • ■ Call the “skipSpaces()” method with “insideWidth” value.
    • ■ Display the “*” character.
    • ■ Increment the “insideWidth” value by 1.
      • ○ Call the “drawBase” method with an argument.
• • Define “drawBase” method.
  • ○ Call the “skipSpaces()” method.
  • ○ Display the “*” character in base of the triangle.
• • Define “skipSpaces()” method.
  • ○ Display the space.
• • Define the “findArea” method.
  • ○ Return the area of right triangle.
• • Define the “findCircumference” method.
  • ○ Return perimeter of the right triangle.

Filename: Rectangle.java

• • Define the “Rectangle.java” class extends from “ShapeBase” class that implements “ShapeInterface”.
• • Include all the methods in the Listing 8.13 in chapter 8.
• • Define another constructor with two parameters.
  • ○ Set the values.
• • Define the “findArea” method.
  • ○ Return the area of rectangle.
• • Define the “findCircumference” method.
  • ○ Return perimeter of the rectangle.

Filename: Square.java

• • Define the “Sqaure.java” class which extends from the “Rectangle” class that implements “ShapeInterface”.
• • Declare the required variables.
• • Define the constructor for the class.
• • Define the accessor and mutator methods.
• • Define the “findArea” method.
  • ○ Return the area of square.
• • Define the “findCircumference” method.
  • ○ Return perimeter of the square.

Filename: ShapeInterface.java

Define the interface “SpaceInterface”.

• • Declare the “setOffset()” method.
• • Declare the “getOffset()” method.
• • Declare the “drawAt()” method.
• • Declare the “drawHere()” method.