public void insert(E data, int id) {
current = first;
for (int i = 0; i < id - 1; i++) {
previous = current;
current = current.getNext();
}
DoubleLinkNode<E> insertedNode = new DoubleLinkNode<E>();
insertedNode.setData(data);
insertedNode.setNext(current);
insertedNode.setPrevious(previous);
boolean isHead = id == 1;
if (isHead) {
first = insertedNode;
} else {
previous.setNext(insertedNode);
DoubleLinkNode<E> originalNode = current;
current = insertedNode;
current.setNext(originalNode);
originalNode.setPrevious(current);
}
size++;
}
/**
* Removes node. If there is no Node with data, it returns silently.
*
* @param data
*/
public void remove(E data) {
loop(data);
if (current == null) {
return;
}
boolean isFirstRemoved = current.getPrevious() == null;
boolean isLastRemoved = current.getNext() == null;
if (isFirstRemoved) {
first = current.getNext();
current = first;
current.setData(null);
} else if (isLastRemoved) {
current = current.getPrevious();
last = current;
current.setNext(null);
} else {
DoubleLinkNode<E> previous = current.getPrevious();
previous.setNext(current.getNext());
current = current.getNext();
current.setPrevious(previous);
}
size--;
}
public void add(E e) {
DoubleLinkNode<E> newNode = new DoubleLinkNode<E>();
newNode.setData(e);
if (size == 0) {
first = newNode;
last = newNode;
current = first;
} else {
previous = last;
last = newNode;
current = newNode;
previous.setNext(newNode);
current.setPrevious(previous);
current.setNext(null);
}
size++;
}
