Homework 02Double Linked List Solution

Write a class called GenDoubleLinkedList which is a generic double linked list.  This link list is similar to the single linked list that was shown in class except that each node in addition to having data and nextLink (which was originally called link) now has prevLink.



The class GenDoubleLinkedList needs to have the following:

Internal class ListNode which has
Instance Variables
data of type T
nextLink of type ListNode
prevLink of type ListNode
Constructors
Default
Parameterized
Instance Variables
head of type ListNode which always points to the beginning of the linked list
current of type ListNode which moves around pointing to one of the nodes
Constructor
A default constructor that initializes head to an empty ListNode and sets current to point at the head.
Methods
goToNext – This moves the current node forward in the list by one node.  It doesn’t move forward if that node is null
goToPrev – This moves the current node backwards in the list by one node.  It doesn’t move backwards if that node is null.
getDataAtCurrent – returns the data at the current node as long as the current isn’t null
setDataAtCurrent – takes in a parameter and sets the data at the current node to that value as long as current is not null
insertNodeAfterCurrent – creates a new node based on data that is passed in by a parameter and puts that node after the current position
deleteCurrentNode – removes the current node from the list by resetting the links
showList – prints out the contents of the list line-by-line
inList – returns a true or false value based on whether or not the data passed in via a parameter is in the list
 

 

Insert Node After Current

 

Delete Current Node

 

 

Finally write a driver that demonstrates each of the methods is working with a double linked list of integers and strings.