package com.levelup.java.exercises.beginner;
import java.util.Scanner;
/**
* This program demonstrates a solution to mass and weight.
*
* @author Justin Musgrove
* @see <a href='http://www.leveluplunch.com/java/exercises/mass-and-weight/'>Mass and weight</a>
*/
public class MassAndWeight {
public static void main(String[] args) {
// Create a Scanner object for keyboard input.
Scanner keyboard = new Scanner(System.in);
// Describe to the user what the program will do.
System.out.println("Enter the object's mass:");
double mass = keyboard.nextDouble();
//close scanner
keyboard.close();
// pass mass to calculate weight
double weight = calculateWeightInNewtons(mass);
System.out.println("The object's weight is: " + weight);
// get message per requirement
String message = validWeight(weight);
if (message.length() > 0) {
System.out.println(message);
}
}
/**
* Method should return a message if weight is greater
* than 1000 or less than 10. If it is between the range
* an empty string will be returned
*
* @param weight
* @return message
*/
static String validWeight (double weight) {
if (weight > 1000) {
return "The object is to heavy";
} else if (weight < 10) {
return "The object is to light";
} else {
return "";
}
}
/**
* Method will calculate weight in Newtons
*
* @param mass
* @return weight
*/
static double calculateWeightInNewtons(double mass) {
return mass * 9.8;
}
}
