Java Lottery - relating arrays to each other

Question

Hello all and thank you for taking the time to read my problem.
I am trying to create a program that asks the user for their name, then how man tickets they would like, then they enter 6 numbers for each ticket.
The maximum amount of 6 number tickets that can be bought is 20.
So for example user1 could get three tickets, user2 could get 10 tickets and user3 could get 7 tickets (20 in total).
My main headache is how to relate the ticket numbers entered with the persons username.
I assume that if user1 gets three tickets these are stored in an array [6] [20] but then when user2 puts their lines on how do I print out at the end who has which tickets?
Also the maximum array size for tickets is [6] [20]...but what if only one user buys 3 tickets and does not use up the remaining 17 tickets, does this affect how I define the array?
Thanks again, all help welcome!

Answer 1

This is sort of what they were talking about, this is an object oriented approach.
There should be no 2D arrays, just arrays of Objects that contain data about themselves or perhaps more Objects.
Try to make your code look more like this.
import java.util.*;
public class Lottery {
    private LinkedList<Person> line = new LinkedList<Person>();
    public Person nextInLine() {
        line.add( new Person() );
        return line.getLast();
    public void showTicketsPurchased() {
        System.out.println( "\nTickets Purchased:");
        for( Person p: line ) {
            p.showTicketsPurchased();
    class Person {
        private LinkedList<Ticket> tickets= new LinkedList<Ticket>();
        void buyTicket( int num1, int num2, int num3, int num4, int num5, int num6 ) {
            try {
                tickets.add( Ticket.sellTicket( num1, num2, num3, num4, num5, num6 ) );
                System.out.println( "Bought Ticket: " + tickets.getLast() );
            } catch (NoSuchElementException nsee) {
                System.out.println( nsee.getMessage() );
                System.out.println( "Could not buy ticket, it's sold out");
        public void showTicketsPurchased() {
            for ( Ticket t: tickets ) {
                System.out.println( t );
    public static void main( String[] args ) {
        Lottery lottery = new Lottery();
        Person servingThisPerson;
        //First person in line
        servingThisPerson = lottery.nextInLine();
        servingThisPerson.buyTicket( 1,2,3,4,5,6 );
        servingThisPerson.buyTicket( 2,3,4,5,6,7 );
        //Second person in line
        servingThisPerson = lottery.nextInLine();
        servingThisPerson.buyTicket( 10, 20, 30, 40, 50, 60 );
        servingThisPerson.buyTicket( 20, 30, 40, 50, 60, 70 );
        lottery.showTicketsPurchased();
import java.util.*;
public class Ticket {
    public static final int MAX_NUM_TICKETS = 20;
    private static int numTicketsSold = 0;
    private int[] numbers;
    private Ticket( int num1, int num2, int num3, int num4, int num5, int num6 ) {
        numbers = new int[]{ num1, num2, num3, num4, num5, num6 };
        numTicketsSold++;
    public static Ticket sellTicket( int num1, int num2, int num3, int num4, int num5, int num6 ) {
        if( numTicketsSold < MAX_NUM_TICKETS ) {
            return new Ticket( num1, num2, num3, num4, num5, num6 );
        } else {
            throw new NoSuchElementException("Tickets sold out");
     * Don't want people to change the tickets numbers after it has been created.
     * @return copy of tickets numbers, not the original array
    public int[] getTicketNumbers() {
        return Arrays.copyOf( numbers, numbers.length );
    public String toString() {
        return Arrays.toString( numbers );
}Brushfire,