Methods

import java.util.Calendar;
import java.util.Scanner;
public class methodsEg
{
    public static void welcome(){
           System.out.println("Welcome!");
    }

    public static int ageIn2020(int a){
           a+=2;
           return a;
    }

    public static int ageIn (int age, int targetYear){
           int year = Calendar.getInstance().get(Calendar.YEAR);
           age+=targetYear-year;
           System.out.println("Current year is " + year);
           return age;
    }

    public static String firstLetter(String n){
           String first = n.substring(0,1);
           return first;
    }

    public static double circleArea(double radius){
            double area = 3.14159*radius*radius;
            return area;
    }

     public static void main(String args[] ) {
       int age;
       String name;
       int year;
       double radius;

       welcome();
       System.out.println("");
       Scanner input = new Scanner(System.in);
       System.out.println("Enter age: ");
       age=input.nextInt();

       System.out.println("Age in 2020 is "+ ageIn2020(age));
       System.out.println("");

       System.out.println("Enter target year: ");
       year=input.nextInt();
       System.out.println("Age in "+year+" will be "+ ageIn(age,year));
       System.out.println("");

       System.out.println("Enter name: ");
       name=input.next();
       System.out.println("The first letter of your name is "+ methodsEg.firstLetter(name));
       System.out.println("");

       System.out.println("Enter radius of circle: ");
       radius=input.nextDouble();
       System.out.println("The area of the circle is " + circleArea(radius));
       System.out.println("");

    }
}