DoubleLinkedList.java

public class DoubleLinkedList {

  private Node head;
  private Node tail;

  public DoubleLinkedList() {
    this.head = null;
    this.tail = null;
  }

  public Node getHead() {
    return head;
  }

  public Node getTail() {
    return tail;
  }

  public void addFirst(int x, int y) {
    Node newNode = new Node(x, y);

    if (head == null)
      head = tail = newNode;
    else {
      newNode.next = head;
      head.prev = newNode;
      head = newNode;
    }
  }

  public void delete(Node n) {
    int x = n.x;
    int y = n.y;
    Node actual = head;

    while (actual != null) {
      if (actual.x == x && actual.y == y) {
        if (actual.prev != null)
          actual.prev.next = actual.next;
        else
          head = actual.next;

        if (actual.next != null)
          actual.next.prev = actual.prev;
        else
          tail = actual.prev;
      }

      actual = actual.next;
    }
  }
}