You can traverse backwards. In a linked list, each node only has a link to the next node. In a doubly linked list, there is also a link to the previous node.
Note that java.util.LinkedList is in fact a doubly linked list.
aruna sameera wrote:i think all ArrayList,LinkedList and vector implement the List interface in java?
is it true?
then how is ArrayList come from array?
A linked list is a type of list. Not all lists are linked lists.
All the List interface tells you is that you can access elements using an index, that the elements are ordered, and that you can traverse it both ways using the ListIterator returned by one of the two listIterator methods. Nothing more, nothing less. How it works internally differs per implementation.