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javacollectionsarraydeque

Sort java.util.Deque


I want to sort the contents of my Deque<Card> collection using the Card class' getRealValue() method.

public class Card implements Comparable<Card> {
  private final int value;
  private final CardType cardType;

  public Card(int value, CardType cardType) {
    this.value = value;
    this.cardType = cardType;
  }

  public int getRealValue() {
    int realValue = this.value == 1 ? 52 : 0;
    return realValue + this.value * 4 + this.cardType.ordinal();
  }

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

Here is my CardType enum

public enum CardType {
    CLUB("♣"),
    SPADE("♠"), 
    HEART("♥"), 
    DIAMOND("♦"); 

    public final String icon;

    private CardType(String icon) {
        this.icon = icon;
    }
}

and I want to sort my Deque based on the realValue()


Solution

  • Well you can always clear it and re-insert the elements in the right order:

    Card[] a = deque.toArray(new Card[0]);
    Arrays.sort(a);
    deque.clear();
    for (Card card : a) {
        deque.add(card);
    }
    

    Bear in mind the performance of this. If sorting is a requirement of your structure, consider using a PriorityQueue.