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public class Card {
  private final int number;

  public Card(int number) {
    this.number = number;
  }

  public boolean equals(Object o) {
    if (!(o instanceof Card)) {
      return false;
    }

    Card c = (Card)o;
    return c.number == number;
  }
}

class XCard extends Card {
  private String type;
  private Card card; // Composition
  
  public XCard(int number, String type) {
    supercard = new Card(number);
    this.type = type;
  }
	  
  public Card viewCard() {
    return card;
  }

  public boolean equals(Object o) {
    if (!(o instanceof XCard)) {
      return false;
    }
      
    XCard cp = (XCard)o;
    return cp.card.equals(card) && cp.type.equals(type);
  }
	  
  public static void main(String[] args) {
    XCard p1 = new XCard(1, "type1");
    Card p2 = new Card(1);
    XCard p3 = new XCard(1, "type2");
    XCard p4 = new XCard(1, "type1");
    System.out.println(p1.equals(p2)); // ReturnsPrints false
    System.out.println(p2.equals(p3)); // ReturnsPrints false
    System.out.println(p1.equals(p3)); // ReturnsPrints false
    System.out.println(p1.equals(p4)); // Prints true
  }
}