Dependencies

C:\Users\Zeeshan>java -version
java version "1.8.0_91"
Java(TM) SE Runtime Environment, Standard Edition (build 1.8.0_91-b15)

1.8.0.91 version of java is used to run this project but this program can be run on previous version as well.

Eclipse Mars 4.5 version
Available at: https://eclipse.org/mars/ 

You can find several Java IDEs or integrated development environments today, employing the use of the right IDE acts as a powerful software development tool for you. i used Eclipse.

• Eclipse

Eclipse is a Java based open source platform that allows a software developer to create a customized development environment (IDE) from plug-in components built by Eclipse members. Eclipse Mars 4.5 version were used and now it supports Java version 8. Can be download Here .

public class LinkedList {
 
    static Node head;
 
    static class Node {
 
        int data;
        Node next;
 
        Node(int d) {
            data = d;
            next = null;
        }
    }
 
    /* Function to reverse the linked list */
    		  
		  
	   YOUR LOGIC HERE
 
}

LinkedList class holds the logic to Reversing list.

class Node {
    Node next = null;
    int data; 

The next holds the next node in a list. If it is the last node, it holds null. The data is a data associated with this node, which in this case is of type int(BTW it should be final).

public Node(int d) {
    data = d;
} 

This is a simple constructor which just copies the argument to its field. It represent the head of the list and a list itself.

Node reverse(Node node) {
       Node prev = null;
       Node current = node;
       Node next = null;
       while (current != null) {
           next = current.next;
           current.next = prev;
           prev = current;
           current = next;
       }
       node = prev;
       return node;
   } 

Create 3 nodes: currNode, PrevNode and nextNode. Initially take three pointers: PrevNode, CurrNode, NextNode currNode = head; nextNode = null;prevNode = null; Let CurrNode point to HeaderNode of the list. And let PrevNode and NextNode points to null Now iterate through the linked list until CurrNode is null In the loop, we need to change NextNode to PrevNode, PrevNode to CurrNode and CurrNode to NextNode Now keep reversing the pointers one by one till currNode!=null.

After First Iteration: After the first iteration of the loop PrevNode points to the node containing element 1 and CurrNode & NextNode points to the node containing element 2. And the node pointed by PrevNode gets unlinked.

After Second Iteration: After the second iteration of the loop, PrevNode Points to the node containing element 2 and CurrNode and NextNode point to the node containing element 3. And the CurrNode next would be pointing to PrevNode. And by the end of the iteration, PrevNode contains the reverse of the complete list

void printList(Node node) {
        while (node != null) {
            System.out.print(node.data + " ");
            node = node.next;
        }
	}

printList is used to prints content of double linked list.

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How to Run Code

To run this program: follow these steps:

Once you downloaded the eclipse and Jdk and Jre installed on machine Start Eclipse: Create a new Java Project.

• File->New->Project and Select "Java" in the category list.
• Select "Java Project" in the project list. Click "Next".
• Enter a project name into the Project name field, for example, Reverses Link List".
• Click "Finish"--It will ask you if you want the Java perspective to open.

Create a new Java class

• Click the Create a Java Class button in the toolbar. (This is the icon below Run and Window with a tooltip that says New Java Class)
• In the dialog give the Class Name I.e. File Name (LinkedList) -Alert it should start with Capital Letter Always
• Then Select main method check box click on Ok. It will create a new class with Public Static Void Main method in it - you can see this in editor Save the file and right click on file and go to Run java. See the console window for output