Using method on arraylist references have unwanted results, Need help!

[chasefooo]

hello im doing a school project for my ap computer programming class and we have to build a program that can deal 20 random cards( doesnt have to be of a 52 card deck) i have it set up so it will create 20 card object containing suit and value and reference them in an arraylist. then uses the deal_one method on each object individually and then prints each card in the array. the problem i am having is that each card printed is exactly the same, not sure why.below is my code.

i plan on using some graphics with it later but now im just trying to get the logic of it right.

/**
 *   this is the driver class for a random card generator that generates 20 random cards 
 * 
 * @author    ___ _                       __  _     _           
 *           / __\ |__   __ _ ___  ___   / _\(_)___| | ___ _ __ 
 *          / /  | '_ \ / _` / __|/ _ \  \ \ | / __| |/ _ \ '__|
 *         / /___| | | | (_| \__ \  __/  _\ \| \__ \ |  __/ |   
 *         \____/|_| |_|\__,_|___/\___|  \__/|_|___/_|\___|_|           
 * @version (2/29/2012)
 */
import java.util.ArrayList;
public class Driver
{


    public  void main (String[] args)
    {
        ArrayList deck = new ArrayList(); 
        Card crd = new Card();
        
        
        Card crd1 = new Card();   
        Card crd2 = new Card(); 
        Card crd3 = new Card(); 
        Card crd4 = new Card(); 
        Card crd5 = new Card(); 
        Card crd6 = new Card(); 
        Card crd7 = new Card(); 
        Card crd8 = new Card();
        Card crd9 = new Card(); 
        Card crd10 = new Card(); 
        Card crd11 = new Card(); 
        Card crd12 = new Card();
        Card crd13 = new Card(); 
        Card crd14 = new Card(); 
        Card crd15 = new Card(); 
        Card crd16 = new Card(); 
        Card crd17 = new Card(); 
        Card crd18 = new Card(); 
        Card crd19 = new Card(); 
        Card crd20 = new Card(); 
            
            deck.add (crd1);       
            deck.add (crd2); 
            deck.add (crd3); 
            deck.add (crd4); 
            deck.add (crd5); 
            deck.add (crd6); 
            deck.add (crd7);  //   <<-- fills the arraylist with 20 Card objects
            deck.add (crd8); 
            deck.add (crd9); 
            deck.add (crd10); 
            deck.add (crd11); 
            deck.add (crd12);
            deck.add (crd13); 
            deck.add (crd14); 
            deck.add (crd15); 
            deck.add (crd16); 
            deck.add (crd17); 
            deck.add (crd18); 
            deck.add (crd19); 
            deck.add (crd20); 

        
        
        for (int x=0;x<20;x++)
        {
            Card y = (Card)deck.get(x);    //
            y.deal_one();                 //     <<--  uses deal_one method to randomize each card in array
            deck.add (x,y);              //            then replaces the card back to the same location
        
        }
        
        for (int x=0;x<20;x++)
        {
            Card current_card = (Card)deck.get (x);
            int val = current_card.get_value();
            
            System.out.println (val);
        }
        
        
        
        
    }
}

/**
 *   the card class has card object 
 * 
 * @author    ___ _                       __  _     _           
 *           / __\ |__   __ _ ___  ___   / _\(_)___| | ___ _ __ 
 *          / /  | '_ \ / _` / __|/ _ \  \ \ | / __| |/ _ \ '__|
 *         / /___| | | | (_| \__ \  __/  _\ \| \__ \ |  __/ |   
 *         \____/|_| |_|\__,_|___/\___|  \__/|_|___/_|\___|_|           
 * @version (2/29/2012)
 */
import java.util.Random;
public class Card
{
    public  Random generator = new Random();
    private int value, suit;
    
    public Card()
    {   
        suit = 1;
        value = 1;
    }
    
    public void deal_one()
    {
        suit = generator.nextInt(4) + 1;
        value = generator.nextInt(13)+1;
    }
    
    public String get_suit()
    {
        String show = "nothing";
        
        int x = suit;
        if (x == 0){show = "Ace";}
        if (x == 1){show = "Heart";}
        if (x == 2){show = "Spade";}
        if (x == 3){show = "Club";}
        
        return show;
    }
    
    public int get_value()
    {
        return value;
    }


    
}

Edit:Also i forgot to ask if there is a better way to instantiate all those objects

[Fubarable]

If it were my program, I wouldn't put any randomization in my Card class but instead would just have that class be the blueprint for creating a single Card object and that's it. I'd not give it a parameterless constructor but rather would have two parameters passed in so that the card rank and suit are determined in the constructor.

[chasefooo]

ok thank you ill try that now and report the results. i like that idea better

[chasefooo]

It Works!! thanks , what do you think about my last question? is there anyway to shorten this?


Card crd2 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd3 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd4 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd5 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd6 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd7 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd8 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd9 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd10 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd11 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd12 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd13 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd14 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd15 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd16 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd17 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd18 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd19 = new Card(b,a); a = generator.nextInt(13)+1; b = generator.nextInt(4)+1;
Card crd20 = new Card(b,a);

deck.add (crd1);
deck.add (crd2);
deck.add (crd3);
deck.add (crd4);
deck.add (crd5);
deck.add (crd6);
deck.add (crd7); // <<-- fills the arraylist with 20 Card objects
deck.add (crd8);
deck.add (crd9);
deck.add (crd10);
deck.add (crd11);
deck.add (crd12);
deck.add (crd13);
deck.add (crd14);
deck.add (crd15);
deck.add (crd16);
deck.add (crd17);
deck.add (crd18);
deck.add (crd19);
deck.add (crd20);

[Fubarable]

Yes, use arrays and a for loop.

[chasefooo]

Sorry i have only been coding for about a month, could you give a little example

[JosAH]

It may be a bit over your head now, but read this tutorial; it has a nice implementation for playing cards.

kind regards,

Jos

[chasefooo]

Thanks! this seems like it will be really useful i cant quite follow it at the moment but im going to book mark it and keep reading it until i understand it.
thanks again everyone i will defiantly be coming back to this forum.

[Tolls]

Since you are not using the 'crd<n>' variables themselves, simply adding them to the array, Fubarable is suggesting you just do a for loop 20 times, generating a card and adding it to the 'deck'.

You already have a for loop in your original code that would do the job, just change the code inside it to create a single card and add it to the deck.