task19

Searching in the Double Linked List

In this task you should implement methods for searching in the Double Linked List collection. You have two classes: the DoubleLinkedList which represents the collection and the Node which represents values. You should implement next methods:

• Node DoubleLinkedList.findByIndex(int index) which takes the int index argument. It should find and return the node with that index (the position on the node in the list like an array's index). If the collection contains such index, the method should return an appropriate node. Is the index is out of bounds, the method should return null.
• Node DoubleLinkedList.findByValue(String value) which takes the String value argument. It should find and return the first node with specified value. It should return null if there are no nodes with such value.