Java program to find circumference and area of a circle :
In this tutorial, we will learn how to find the area and circumference of a circle using Java. We only need the radius of the circle to find both of these values. Area is _‘PIradiusradius’_and circumference is ‘2PIradius’. Let’s take a look how to calculate these values :
Java Program :
import java.util.Scanner;
public class Main {
/**
* Utility function for System.out.println
*
* @param message : string to print
*/
private static void println(String message) {
System.out.println(message);
}
/**
* Utility function for System.out.print
*
* @param message : string to print
*/
private static void print(String message) {
System.out.print(message);
}
/**
* main method
*
* @throws java.lang.Exception
*/
public static void main(String[] args) throws java.lang.Exception {
//1
double radius, area, circumference;
//2
Scanner scanner = new Scanner(System.in);
//3
print("Enter the radius of the circle : ");
radius = scanner.nextDouble();
//4
area = Math.PI * radius * radius;
circumference = 2 * Math.PI * radius;
//5
System.out.printf("Area of the circle : %.2f", area);
println("");
System.out.printf("Circumference of the circle :%.2f ", circumference);
}
}
Sample Output :
Enter the radius of the circle : 100
Area of the circle : 31415.93
Circumference of the circle :628.32
Enter the radius of the circle : 19.4
Area of the circle : 1182.37
Circumference of the circle :121.89
Enter the radius of the circle : 10
Area of the circle : 314.16
Circumference of the circle :62.83
Explanation :
-
Create three ’double’ variables to store the radius, area and circumference of the circle.
-
Create one ’Scanner’ object to take the inputs from the user.
-
Read the ’radius’ of the circle.
-
Find out the area and circumference and save the values to ’area’ and ’circumference’ variables. We are using ‘Math.PI’ for the value of ’PI‘.
-
Print out the values of area and circumference calculated.