Here is an example of Temperature Conversion where we have converted Celcius to Fahrenheit and vice versa. For this, we have create three functions celcius(), fahrenheit() and display table which display the conveted values in the form of chart.

import java.util.*;
import java.text.*;

class Degrees 
{
    public static double fahrenheit(int temp) {
         return (1.8 * temp) + 32;
    }

    public static double celsius(int temp) {
         return (temp - 32) / 1.8;
    }
    public static void displayTable(){
        DecimalFormat df=new DecimalFormat("##.#");
        System.out.println("Celcius (C)   Fahrenheit (F)");
        for(int i=0;i<=100;i+=4){
            System.out.println(i+"\t    |     "+df.format(fahrenheit(i)));
        }
        System.out.println("Fahrenheit (F)   Celcius (C) ");
        for(int i=32;i<=212;i+=10){
            System.out.println(i+"\t    |     "+df.format(celsius(i)));
        }
    }

    public static void main(String[] args) 
    {
        displayTable();
    }
}

thanks :)