Add Default method for interface - Java Object Oriented Design

Description

Add Default method for interface

Demo Code

import java.util.*;
import java.util.stream.*;
import java.lang.*;
import java.util.function.*;

 interface SortFunction extends Function<Comparator<Card>, Deck> {
    public Deck apply(Comparator<Card> cardComparator);
}

class SortByRankThenSuit implements Comparator<Card> {
    public int compare(Card firstCard, Card secondCard) {
        int compVal = firstCard.getRank().value()
                - secondCard.getRank().value();
        if (compVal != 0)
            return compVal;
        else/*from   w  w w . ja  v a2 s .  c om*/
            return firstCard.getSuit().value()
                    - secondCard.getSuit().value();
    }
}
 interface Deck {

    List<Card> getCards();

    Deck deckFactory();

    int size();

    void addCard(Card card);

    void addCards(List<Card> cards);

    void addDeck(Deck deck);

    void shuffle();

    void sort();

    void sort(Comparator<Card> c);

    String deckToString();

    Map<Integer, Deck> deal(int players, int numberOfCards)
            throws IllegalArgumentException;

}
interface Card extends Comparable<Card> {

    public enum Suit {
        DIAMONDS(1, "Diamonds"), CLUBS(2, "Clubs"), HEARTS(3, "Hearts"), SPADES(
                4, "Spades");

        private final int value;
        private final String text;

        Suit(int value, String text) {
            this.value = value;
            this.text = text;
        }

        public int value() {
            return value;
        }

        public String text() {
            return text;
        }
    }

    public enum Rank {
        DEUCE(2, "Two"), THREE(3, "Three"), FOUR(4, "Four"), FIVE(5, "Five"), SIX(
                6, "Six"), SEVEN(7, "Seven"), EIGHT(8, "Eight"), NINE(9,
                "Nine"), TEN(10, "Ten"), JACK(11, "Jack"), QUEEN(12,
                "Queen"), KING(13, "King"), ACE(14, "Ace");
        private final int value;
        private final String text;

        Rank(int value, String text) {
            this.value = value;
            this.text = text;
        }

        public int value() {
            return value;
        }

        public String text() {
            return text;
        }
    }

    public Card.Suit getSuit();

    public Card.Rank getRank();
}
 class PlayingCard implements Card {

    private Card.Rank rank;
    private Card.Suit suit;

    public PlayingCard(Card.Rank rank, Card.Suit suit) {
        this.rank = rank;
        this.suit = suit;
    }

    public Card.Suit getSuit() {
        return suit;
    }

    public Card.Rank getRank() {
        return rank;
    }

    public boolean equals(Object obj) {
        if (obj instanceof Card) {
            if (((Card) obj).getRank() == this.rank
                    && ((Card) obj).getSuit() == this.suit) {
                return true;
            } else {
                return false;
            }
        } else {
            return false;
        }
    }

    public int hashCode() {
        return ((suit.value() - 1) * 13) + rank.value();
    }

    public int compareTo(Card o) {
        return this.hashCode() - o.hashCode();
    }

    public String toString() {
        return this.rank.text() + " of " + this.suit.text();
    }

    public static void main(String... args) {
        new PlayingCard(Rank.ACE, Suit.DIAMONDS);
        new PlayingCard(Rank.KING, Suit.SPADES);
    }
}

 class StandardDeck implements Deck {

    private List<Card> entireDeck;

    public StandardDeck(List<Card> existingList) {
        this.entireDeck = existingList;
    }

    public StandardDeck() {
        this.entireDeck = new ArrayList<>();
        for (Card.Suit s : Card.Suit.values()) {
            for (Card.Rank r : Card.Rank.values()) {
                this.entireDeck.add(new PlayingCard(r, s));
            }
        }
    }

    public Deck deckFactory() {
        return new StandardDeck(new ArrayList<Card>());
    }

    public int size() {
        return entireDeck.size();
    }

    public List<Card> getCards() {
        return entireDeck;
    }

    public void addCard(Card card) {
        entireDeck.add(card);
    }

    public void addCards(List<Card> cards) {
        entireDeck.addAll(cards);
    }

    public void addDeck(Deck deck) {
        List<Card> listToAdd = deck.getCards();
        entireDeck.addAll(listToAdd);
    }

    public void sort() {
        Collections.sort(entireDeck);
    }

    public void sort(Comparator<Card> c) {
        Collections.sort(entireDeck, c);
    }

    public void shuffle() {
        Collections.shuffle(entireDeck);
    }

    public Map<Integer, Deck> deal(int players, int numberOfCards)
    throws IllegalArgumentException
{
    int cardsDealt = players * numberOfCards;
    int sizeOfDeck = entireDeck.size();
    if (cardsDealt > sizeOfDeck) {
        throw new IllegalArgumentException(
            "Number of players (" + players +
            ") times number of cards to be dealt (" + numberOfCards +
            ") is greater than the number of cards in the deck (" +
            sizeOfDeck + ").");
    }
        
    Map<Integer, List<Card>> dealtDeck = entireDeck
       .stream()
       .collect(
           Collectors.groupingBy(
               card -> {
                   int cardIndex = entireDeck.indexOf(card);
                   if (cardIndex >= cardsDealt) return (players + 1);
                   else return (cardIndex % players) + 1;
               }));
        
    // Convert Map<Integer, List<Card>> to Map<Integer, Deck>
    Map<Integer, Deck> mapToReturn = new HashMap<>();
           
    for (int i = 1; i <= (players + 1); i++) {
        Deck currentDeck = deckFactory();
        currentDeck.addCards(dealtDeck.get(i));
        mapToReturn.put(i, currentDeck);
    }
    return mapToReturn;
}

    public String deckToString() {
    return this.entireDeck
        .stream()
        .map(Card::toString)
        .collect(Collectors.joining("\n"));
}

    public static void main(String... args) {
    StandardDeck myDeck = new StandardDeck();
    System.out.println("Creating deck:");
    myDeck.sort();
    System.out.println("Sorted deck");
    System.out.println(myDeck.deckToString());
    myDeck.shuffle();
    myDeck.sort(new SortByRankThenSuit());
    System.out.println("Sorted by rank, then by suit");
    System.out.println(myDeck.deckToString());        
    myDeck.shuffle();
    myDeck.sort(
        Comparator.comparing(Card::getRank)
            .thenComparing(Comparator.comparing(Card::getSuit)));
    System.out.println("Sorted by rank, then by suit " +
        "with static and default methods");
    System.out.println(myDeck.deckToString());        
    myDeck.sort(
        Comparator.comparing(Card::getRank)
            .reversed()
            .thenComparing(Comparator.comparing(Card::getSuit)));
    System.out.println("Sorted by rank reversed, then by suit " +
        "with static and default methods");
    System.out.println(myDeck.deckToString());
}
}


/*
 * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *   - Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 *   - Neither the name of Oracle or the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

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