Introduction

In this guide, we will create separate Java programs to calculate the area of a square, rectangle, and triangle. Each program will prompt the user to enter the necessary dimensions for the respective shape and then compute and display the area.

Problem Statement

Create separate Java programs that:

Calculate the area of a square given the length of its side.
Calculate the area of a rectangle given its length and width.
Calculate the area of a triangle given its base and height.

Example 1: Area of Square

Input: Side = 5
Output: Area = 25

Example 2: Area of Rectangle

Input: Length = 10, Width = 5
Output: Area = 50

Example 3: Area of Triangle

Input: Base = 8, Height = 6
Output: Area = 24

Program 1: Calculate the Area of a Square

Java Program

import java.util.Scanner;

/**
 * Java Program to Calculate Area of Square
 * Author: https://www.javaguides.net/
 */
public class SquareAreaCalculator {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        // Prompt for the side length of the square
        System.out.print("Enter the side of the square: ");
        double side = scanner.nextDouble();

        // Calculate the area of the square
        double squareArea = side * side;

        // Display the result
        System.out.println("Area of the square: " + squareArea);
    }
}

Output Example

Enter the side of the square: 5
Area of the square: 25.0

Explanation

Input: The program prompts the user to enter the side length of the square.
Calculation: It calculates the area using the formula ( \text{Area} = \text{side} \times \text{side} ).
Output: The calculated area is then displayed to the user.

Program 2: Calculate the Area of a Rectangle

Java Program

import java.util.Scanner;

/**
 * Java Program to Calculate Area of Rectangle
 * Author: https://www.javaguides.net/
 */
public class RectangleAreaCalculator {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        // Prompt for the length and width of the rectangle
        System.out.print("Enter the length of the rectangle: ");
        double length = scanner.nextDouble();
        System.out.print("Enter the width of the rectangle: ");
        double width = scanner.nextDouble();

        // Calculate the area of the rectangle
        double rectangleArea = length * width;

        // Display the result
        System.out.println("Area of the rectangle: " + rectangleArea);
    }
}

Output Example

Enter the length of the rectangle: 10
Enter the width of the rectangle: 5
Area of the rectangle: 50.0

Explanation

Input: The program prompts the user to enter the length and width of the rectangle.
Calculation: It calculates the area using the formula ( \text{Area} = \text{length} \times \text{width} ).
Output: The calculated area is displayed to the user.

Program 3: Calculate the Area of a Triangle

Java Program

import java.util.Scanner;

/**
 * Java Program to Calculate Area of Triangle
 * Author: https://www.javaguides.net/
 */
public class TriangleAreaCalculator {

    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        // Prompt for the base and height of the triangle
        System.out.print("Enter the base of the triangle: ");
        double base = scanner.nextDouble();
        System.out.print("Enter the height of the triangle: ");
        double height = scanner.nextDouble();

        // Calculate the area of the triangle
        double triangleArea = 0.5 * base * height;

        // Display the result
        System.out.println("Area of the triangle: " + triangleArea);
    }
}

Output Example

Enter the base of the triangle: 8
Enter the height of the triangle: 6
Area of the triangle: 24.0

Explanation

Input: The program prompts the user to enter the base and height of the triangle.
Calculation: It calculates the area using the formula ( \text{Area} = 0.5 \times \text{base} \times \text{height} ).
Output: The calculated area is displayed to the user.

Conclusion

These Java programs provide a simple and effective way to calculate the area of a square, rectangle, and triangle individually. By separating the programs, each is easy to understand, test, and maintain. This approach also allows for easy modifications or enhancements specific to each shape's area calculation.