# Area of Circle Java

Hey guys!! Welcome to flower brackets. Today we are going to learn area of circle java.

Decades ago we have seen and learnt area of circle in our school in geometry class.

Also Read – Area of Rectangle Program in Java

I still remember the way how our geometry teacher explained the concept of area of a circle using compass and measuring the radius using ruler.

Good’ol days… Now we will see java area of a circle.

#### example: area of circle java

// Area of circle is, area = pi * r * r where r is the radius of a circle

```import java.io.BufferedReader;
import java.io.IOException;

public class AreaOfCircle
{
public static void main(String[] args)
{
System.out.println("Enter the radius of a Circle: ");
try
{
}
// To check whether invalid value was entered
catch(NumberFormatException nfe)
{
System.exit(0);
}
catch(IOException ioe)
{
System.out.println("IO Error: " + ioe);
System.exit(0);
}
System.out.println("Area of a circle is " + circleArea);
}
}

```

Output:
Enter the radius of a Circle: 10
Area of a circle is 314.1592653589793

#### to calculate circumference: area of circle java

Now in area of circle in java let’s see java program to calculate area and circumference of circle.

```import java.util.Scanner;

public class CircleCircumference
{
public static void main(String[] args)
{
// Here we are declaring Scanner class which could read from console
Scanner sc = new Scanner(System.in);
double circumference = 0.0;
// Formula for calculating circumference of circle
// circumference = 2 * 22 / 7 * radius
circumference = 2 * Math.PI * radius;
System.out.println("Circumference of circle is : " + circumference);
}
}

```

Output:

Circumference of circle is : 31.41592653589793

#### to calculate area of circle using method

Here we are going to see java program to calculate area of circle using method.

```import java.util.Scanner;

public class AreaOfCircleDemo
{
public static void main(String[] args)
{
Scanner sc = new Scanner(System.in);
System.out.println("The area of circle is : " + area);
sc.close();
}

static double calculateArea(double r)
{
return (22 * r * r) / 7;
}
}

```

Output:

The area of circle is : 314.2857142857143

Another way

Now let’s learn how to find circumference of circle with area. Here’s the code calculate area of circle from circumference,

```public class CircleJava
{
public static void main(String[] args)
{
System.out.println("The area of a circle in java : " + area);
double circumference = Math.PI * 2 * radius;
System.out.println("Circumference of circle : " + circumference) ;
}
}

```

Output:

The area of a circle in java : 78.53981633974483
Circumference of circle : 31.41592653589793

##### conclusion

So this is all about area of circle java. I hope you guys have understood java program to calculate area of circle using method.

You can subscribe to my blog flower brackets if haven’t already.