CMSC 132, Object-Oriented Programming II Summer 2017
Lecture 8:
Lecturer: Anwar Mamat
Disclaimer:These notes may be distributed outside this class only with the permission of the Instructor.
8.1 Doubly Linked List
Like a singly linked list, a doubly-linked list is a linked data structure that consists of a set of sequentially
linked records called nodes. Unlike a singly linked list, each node of the doubly singly list contains two fields
that are references to the previous and to the next node in the sequence of nodes. The beginning and ending
nodes’ previous and next links, respectively, point to some kind of terminator, typically a sentinel node or
null, to facilitate traversal of the list.
Listing 1: Doubly Linked List Node Class
1class Node<E>{
2E data;
3Node previous;
4Node next;
5Node(E item){
6data = item;
7}
8}
Usually Node class is nested inside the LinkedList class, and members of Node are private.
8.1.1 Create a simple linked list
Now, let us create a simple linked list.
1Node<String> n1 = new Node("Alice");
2Node<String> n2 = new Node("Bob");
3Node<String> n3 = new Node("Cathy");
4n1.next = n2;
5n2.previous = n1;
6n2.next = n3;
7n3.previous = n2;
This linked list represents this:
Alice Bob Cathy
8.1.2 Display the Linked List
We can display all the linked list:
8-1
