Hellow guys, welcom to Lingarajtechhub.Today we are going to discuss find area of circle by user input in java.
Code:
package com.operators.java; import java.util.Scanner; public class Area_of_circle { public static void main(String[] args) { double area,radius; Scanner sc =new Scanner (System.in); System.out.println("Enter the radius of circle :"); radius=sc.nextDouble(); double pi = 3.14; area = pi* radius* radius; System.out.println("Area of the circle :"+area); } }
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package com.Operators.Java;
- It is a java package which is a collection of classes and this package is created in a java project(Homework_operator) .
- Here com.operators.java is the name of our package.
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import java.util.Scanner;
- Scanner is a class in java
- . util package used for obtaining the input of the primitive types like int, double, etc. and strings .
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public class Area_of_circle
- Here “Area_of_circle” is defined as a class which is a template used to create objects ,& to define object ,data type and method.
- It is defined as public because it can be accessed anywhere.
- It is the entry point to the application.
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public static void main(String[] args){
- This is the main () method of our java program .
- Every java program must contain the main() method .
- Public : It is the access modifier of the main function which must be public so that the JRE can access and execute this method.
- If a method is not public then access is restricted and its showing error.
- Static : Static is a keyword in which the main method has to be static in which JVM can load the class into memory and call the main method without creating an instance .
- Void : It means no return types.
- Main() : It is a function.
- String [] args :String means collection of characters
- String[] args represents a collection of Strings ,that are separated by a space and can be typed into the program on the terminal directly.
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double radius ,area ;
- Here we Declare 2 variable radius ,area which is double type and double is a local variable.
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- Scanner Sc = new Scanner(System.in);
- Here scanner is a class and Sc is the instance of the object which is the new Scanner. System.in is an argument.
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radius=sc.nextDouble();
- “radius” is a variable that we take and sc is our instance name which is created for an object and nextDouble() is a method of a Scanner object that reads in a string of digits or char and converts them into an double type.
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System.out.println(” Area of the circle “+area);
- It means System is a class name and out is an instance of the System println is to print a new line and “+” means cocardinate .