/*
This is a first Java program that takes a parameter from
the command line and depending on the value given produces
varying results. It's designed to show the flow and structure
of a very easy first Java program - but in the spirit of Java
with heavy use of named pieces of code (functions) all included
within a class.

Note - this program does not include data validation so if the
user fails to run it with an integer parameter, and untrapped
exception will be thrown (i.e. you'll get a messy Java error
message and the program will stop at that point!)
*/

public class Chloe {

        public static void main(String [] args) {
                System.out.println("Welcome to the world of Java");
                System.out.println("What would you like to drink?");

                // First use of a variable
                // Collect a whole number from the command line's
                // first String

                // age will be an "integer" a.k.a. int

                int age = Integer.parseInt(args[0]);
                System.out.print("We are working for age ");
                System.out.print(age);
                System.out.println(" years");

                softdrink();

                // Pass the age into harddrink so that we don't
                // offer the strong stuff to the young. We need
                // to pass it in so that it's available within
                // harddrink

                harddrink(age);
        }

        public static void softdrink() {
                System.out.println("\nFor the whole family");
                System.out.println("Coca Cola");
                System.out.println("Coffee");
                System.out.println("Milk");
                System.out.println("Water");
                }

        public static void harddrink(int personsAge) {
                // Incoming parameter will be called personsAge
                // Could be the same name as the name in the calling
                // code or a different one.
                if (personsAge >= 18) {
                        System.out.println("\nMummsies and Daddsies only");
                        System.out.println("Beer");
                        System.out.println("Wine");
                        System.out.println("Vodka");
                        System.out.println("Meths");
                        }
                }
}

/* ----------------------------- Sample outputs

Dorothy-2:java grahamellis$ java Chloe
Welcome to the world of Java
What would you like to drink?
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
        at Chloe.main(Chloe.java:19)
Dorothy-2:java grahamellis$ java Chloe 10
Welcome to the world of Java
What would you like to drink?
We are working for age 10 years

For the whole family
Coca Cola
Coffee
Milk
Water
Dorothy-2:java grahamellis$ java Chloe 18
Welcome to the world of Java
What would you like to drink?
We are working for age 18 years

For the whole family
Coca Cola
Coffee
Milk
Water

Mummsies and Daddsies only
Beer
Wine
Vodka
Meths
Dorothy-2:java grahamellis$

*/