Card Game Adding cards to a set of "hands" --Java

Question

I am trying to make a basic outline for a card game, I have the deck created, a method created for dealing a random card but I am having difficulty for adding the card into the actual hand. The issue is in the Game class with the getCard() method. I do not know the correct way to do this, since my idea did not work.

Class to create the deck:

import java.util.Random;

public class Deck<E> {

//create a new linked list for Deck
LinkedPositionalList deck = new LinkedPositionalList();

public Deck(){
    for (int i = 0; i < 4; i++){
        for(int j = 2; j< 14; j++){
            Card card = new Card(i,j);
            deck.addLast(card); //add to linked list
        }
    }
}

public Card card(){
    Random rand = new Random();
    int position = rand.nextInt(52);//create random number 0-52
    int counter = 0;
    Iterator<Card> iter = this.deck.iterator();

    while(counter <= position){
        Card card = iter.next();
        if(counter == position){
            iter.remove();
            return card;
        }
        counter++;
    }
    return null;
}
}

Class to create the card:

public class Card<E> {
public final static int CLUBS  = 0,
                        SPADES = 1,
                        DIAMONDS = 2,
                        HEARTS = 3;
private final static String [] suitNames = {"CLUBS", "SPADES", "DIAMONDS", "HEARTS"};

// Special cards
private int JACK_VALUE = 11;
private int QUEEN_VALUE = 12;
private int KING_VALUE = 13;
private int ACE_VALUE = 14;

// The card
private int suit = 0;           // Suit of the card
private int value = 2;          // Value of the card

public int getSuit() {
    return this.suit;
}

public int getValue() {
    return this.value;
}

public Card(int suit, int value ){

    this.suit = suit;
    this.value = value;
}

public String suitToString() {
    return suitNames[ suit ];
}

public String valueToString() {
    if (value == ACE_VALUE) {
        return "ACE";
    } else if (value == JACK_VALUE) {
        return "JACK";
    } else if (value == QUEEN_VALUE) {
        return "QUEEN";
    } else if (value == KING_VALUE) {
        return "KING";
    } else if ( value > 0 ) {
        return String.valueOf(value);
    }
    return "";
}

public String shortValueToString() {
    if (value == ACE_VALUE) {
        return " A";
    } else if (value == JACK_VALUE) {
        return " J";
    } else if (value == QUEEN_VALUE) {
        return " Q";
    } else if (value == KING_VALUE) {
        return " K";
    } else if ( value > 0 ) {
        return String.format("%2d",value);
    }
    return "";
}

public String toString() {
    return valueToString() + " of " + suitToString();
}

public String toShortString() {
    return shortValueToString() + suitToString().substring(0,1);
}

public boolean equalTo(Card c ) {
    if ( c.getSuit() != this.getSuit()) return false;
    if ( c.getValue() != this.getValue()) return false;
    return true;
}
}

Class to create the hand:

public class CardHand<E> {

LinkedPositionalList<E> hand = new LinkedPositionalList();
//TODO: create method to order hand
}

Class to initialize the game:

public class Game{
    int players;
    int maxCardsInHand;
    int decks;
    CardHand[] hand;
    Card card;
    Deck deck;

//constructor
public Game(int player, int max, int numDecks){
    players = player;
    maxCardsInHand = max;
    decks = numDecks;
    this.hand = new CardHand[player];
    for(int index = 0; index < hand.length; index++){
        this.hand[index] = new CardHand();
    }
}

public void getCard(){
    System.out.println("You got this far...");
    card = deck.card();
    for(int index = 0; index < hand.length;  index++){ //to add to each players hands
        hand[index] = card; //issues with this part
    }
    //TODO: ordered correctly by suit AND value
}

First, `card` should be local variable in the `getCard()` method. Second, what issues do you run into? — Stefan, Oct 13 '17 at 14:34
@Stefan I am getting a null pointer exception. My output prints "You got this far". I need to make the call to deck.card(); because that actually deals the card — Travis, Oct 13 '17 at 14:35
Possible duplicate of [What is a NullPointerException, and how do I fix it?](https://stackoverflow.com/questions/218384/what-is-a-nullpointerexception-and-how-do-i-fix-it) — GriffeyDog, Oct 13 '17 at 14:37

Stefan · Answer 1 · 2017-10-13T14:44:43.757

1

Given that the call iter.remove(); works, your deck gets smaller and smaller each time you call the card() method. Yet you assume you can iterate thru a full deck:

rand.nextInt(52);

Instead, iterate only over the cards you have left:

rand.nextInt(this.deck.size());

If there is no size() or length() method for the list object, decrease a counter each time card() is called:

rand.nextInt(cardsInDeck++);

edited Oct 13 '17 at 14:44

answered Oct 13 '17 at 14:38

Stefan

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I need to use a positional linked list for this. – Travis Oct 13 '17 at 14:41

Card Game Adding cards to a set of "hands" --Java

1 Answers1