Java program to find Area of Circle

 Java is a powerful programming language that allows developers to create a wide range of applications. One of the most common calculations that programmers need to make is finding the area of a circle. In this blog post, we will go over how to write a Java program that calculates the area of a circle using the formula pi x radius x radius.

The first step in creating our program is to import the necessary libraries. In this case, we will need to import the Math library, which contains the value for pi. We will also need to import the Scanner library, which will allow us to take input from the user.

import java.util.Scanner; 
import java.lang.Math;

Next, we will create a class called "CircleArea" and define our main method within it. In the main method, we will create a new instance of the Scanner class to take input from the user. We will then prompt the user to enter the radius of the circle and store the value in a variable called "radius".

public class CircleArea {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the radius of the circle: ");
        double radius = scanner.nextDouble();
    }
}

Now that we have the radius of the circle, we can use the formula pi x radius x radius to calculate the area. We will use the Math.PI constant to get the value of pi and store the result in a variable called "area".

double area = Math.PI * radius * radius;

Finally, we will print out the result to the user.

System.out.println("The area of the circle is: " + area);

The complete code for the program is as follows:

import java.util.Scanner;
import java.lang.Math;

public class CircleArea {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        System.out.print("Enter the radius of the circle: ");
        double radius = scanner.nextDouble();
        double area = Math.PI * radius * radius;
        System.out.println("The area of the circle is: " + area);
    }
}

When you run this program, it will ask the user to enter the radius of the circle and then print out the area of the circle. This program is a simple example of how you can use Java to perform calculations and take user input.

In conclusion, Java is a powerful programming language that allows developers to perform a wide range of calculations. In this blog post, we have gone over how to write a program that calculates the area of a circle using the formula pi x radius x radius. Remember to import the necessary libraries and to use the Math.PI constant to get the value of pi. Happy coding!