Java LinkedList Example
In this section we will discuss about the own implementation of Linked List in Java.
Linked List is a part of Data Structure. In Linked List nodes are connected by a link this link is referred to as one node contains the reference of next node. In this tutorial we will learn this by a simple example. In this example we will display an original list and then display its reverse order.
Example
Here I am going to give a simple example which demonstrate how nodes are linked to each other and how can we displayed in their order as well as in its reverse order. In this example I have created Java classes. The Java class Link instantiates a reference variable next which will be used for linking the next value in the list. Then created a class named LinkList where written methods for printing the list value in its order and its reverse order. Then created a main class where created the list values and called methods for displaying list values.
Source Code
class Link
{
Link next;
String num;
Link (String num )
{
this.num = num;
}
public String toString()
{
return num;
}
}// close Link class
class LinkList
{
Link first;
public void print(Link node)
{
System.out.print (node);
if (node.next!=null)
{
System.out.print (" -> ");
print(node.next);
}
}
public void reverseList()
{
Link node3 = first;
Link node2 = null;
Link node1 = null;
while (node3!= null)
{
node1 = node2;
node2 = node3;
node3 = node2.next;
node2.next = node1;
}
first = node2;
}
}// close LinkList
public class JavaSinglyLinkList
{
public static void main (String args[])
{
Link l1 = new Link("1");
Link l2 = new Link("2");
Link l3 = new Link("3");
Link l4 = new Link("4");
Link l5 = new Link("5");
l1.next = l2;
l2.next = l3;
l3.next = l4;
l4.next = l5;
LinkList LL = new LinkList();
LL.first = l1;
System.out.println ("\nCurrent list");
LL.print(LL.first);
LL.reverseList();
System.out.println();
System.out.println ("\nList in reverse order");
LL.print(LL.first);
System.out.println();
}
}
Output
When you will execute the JavaSinglyLinkList.java then the output will be as follows :
