/**
* Returns the data stored at the specified index.
*
* @param index The index determines the node whose data is returned.
* @return Returns the data of the node at the index.
*/
public E get(int index) { // returns the data stored at the specified index
int currIndex = 0;
DoubleLinkedNode<E> currNode = this.head;
E temp = null;
if (index == 0) { // zero case
temp = currNode.getData();
} else if (index > 0) { // positive
while (currIndex != size) {
if (currIndex != index % size) {
currIndex++;
currNode = currNode.getNext();
} else {
temp = currNode.getData();
break;
}
}
} else if (index < 0) { // negative
while (currIndex != -size) {
if (currIndex != index % size) {
currIndex--;
currNode = currNode.getPrev();
} else {
temp = currNode.getData();
break;
}
}
}
return temp;
}
/**
* Which removes and returns an item from the list.
*
* @param index Removes the node at the current index.
* @return Returns the data of the removed node.
*/
public E remove(int index) { // which removes and returns an item from the list
int currIndex = 0;
DoubleLinkedNode<E> currNode = this.head;
DoubleLinkedNode<E> nextNode = this.head.getNext();
DoubleLinkedNode<E> prevNode = this.head.getPrev();
E temp = null;
if (index == 0) {
temp = currNode.getData();
prevNode.setNext(currNode.getNext());
nextNode.setPrev(currNode.getPrev());
this.head = nextNode;
size--;
} else if (index > 0) { // positive
while (currIndex != size) {
if (currIndex != index % size) {
currIndex++;
currNode = currNode.getNext();
nextNode = nextNode.getNext();
prevNode = prevNode.getNext();
} else {
temp = currNode.getData();
prevNode.setNext(currNode.getNext());
nextNode.setPrev(currNode.getPrev());
currNode = nextNode;
size--;
break;
}
}
} else if (index < 0) { // negative
while (currIndex != -size) {
if (currIndex != index % size) {
currIndex--;
currNode = currNode.getPrev();
prevNode = prevNode.getPrev();
nextNode = nextNode.getPrev();
} else {
temp = currNode.getData();
prevNode.setNext(currNode.getNext());
nextNode.setPrev(currNode.getPrev());
currNode = prevNode;
size--;
break;
}
}
}
return temp;
}
@Override
public E previous() {
if (!hasPrevious()) {
throw new NoSuchElementException("No such element.");
} else {
prevItem = head;
lastReturned = prevItem.getPrev();
prevItem = prevItem.getPrev();
head = prevItem;
index--;
return lastReturned.getData();
}
}
@Override
public E next() {
if (!hasNext()) {
throw new NoSuchElementException("No such element.");
} else {
nextItem = head;
lastReturned = nextItem;
nextItem = nextItem.getNext();
head = nextItem;
index++;
return lastReturned.getData();
}
}
@Override
public String toString() {
String str = "[";
int index = 0;
DoubleLinkedNode<E> curr = head;
if (size == 0) {
return "There is no one here to kill.";
} else {
while (index < size) {
str += curr.getData();
curr = curr.getNext();
index++;
if (index < size) {
str += ", ";
}
}
str += "]";
}
return str;
}