Java: Print the area and perimeter of a rectangle

Last update on April 01 2025 10:51:29 (UTC/GMT +8 hours)

Rectangle: Area and Perimeter

Write a Java program to print the area and perimeter of a rectangle.

Java: Perimeter of a rectangle

A perimeter is a path that surrounds a two-dimensional shape. The word comes from the Greek peri (around) and meter (measure). The perimeter can be used to calculate the length of fence required to surround a yard or garden. Following image represents the perimeter of a rectangle.

Java: Area of a rectangle

In Euclidean plane geometry, a rectangle is a quadrilateral with four right angles. To find the area of a rectangle, multiply the length by the width.
A rectangle with four sides of equal length is a square.
Following image represents the area of a rectangle.

Pictorial Presentation:

Sample Solution:

Java Code:

public class Exercise13 { 
   public static void main(String[] strings) {
        // Define constants for the width and height of the rectangle
        final double width = 5.6;
        final double height = 8.5;

        // Calculate the perimeter of the rectangle
        double perimeter = 2 * (height + width);
		
        // Calculate the area of the rectangle
        double area = width * height;			

        // Print the calculated perimeter using placeholders for values
        System.out.printf("Perimeter is 2*(%.1f + %.1f) = %.2f \n", height, width, perimeter);

        // Print the calculated area using placeholders for values
        System.out.printf("Area is %.1f * %.1f = %.2f \n", width, height, area);
    }
}

Explanation:

In the exercise above -

• Define constant values for the rectangle's width (5.6) and height (8.5).
• Calculate the rectangle perimeter using the formula: 2 * (height + width).
• Calculate the rectangle area using the formula: width * height.
• Prints the perimeter and area values to the console using printf statements with formatted output to display the results with specific decimal precision.

Sample Output:

Perimeter is 2*(8.5 + 5.6) = 28.20 
Area is 5.6 * 8.5 = 47.60 

Flowchart:

For more Practice: Solve these Related Problems:

• Write a program to calculate the area and perimeter of a parallelogram.
• Modify the program to accept user input for both width and height.
• Write a program that calculates the area and perimeter of a rectangle with decimal values.
• Compute the diagonal length of a rectangle using the Pythagorean theorem.

Java Code Editor:

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