LinkedList_Execution.java

/*   Created by IntelliJ IDEA.
 *   Author: Kshitij Varshney (kshitijvarshne1)
 *   Date: 08-Feb-21
 *   Time: 11:00 AM
 *   File: Execution.java
 */

package feb08_21_NK.LinkedList;


public class Execution {
    public static void main(String[] args) {
        SinglyLinkedList list = new SinglyLinkedList();
        for (int i = 0; i < 5; i++) {
            list.insertAtBegin(new Node(i));
        }
       // list.printSinglyLinkedList();
        Node n1 = new Node(1000);
        list.insertAtEnd(n1);
        //list.printSinglyLinkedList();
        n1.data= 44;
        list.insertAtBegin(n1);
        //list.insertAtEnd(n1);
        list.printSinglyLinkedList();
    }

}

LinkedList_Node.java

/*   Created by IntelliJ IDEA.
 *   Author: Kshitij Varshney (kshitijvarshne1)
 *   Date: 08-Feb-21
 *   Time: 10:55 AM
 *   File: Node.java
 */

package feb08_21_NK.LinkedList;

public class Node {
    int data;
    Node next; // self reference structure

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

LinkedList_SinglyLinkedList.java

/*   Created by IntelliJ IDEA.
 *   Author: Kshitij Varshney (kshitijvarshne1)
 *   Date: 08-Feb-21
 *   Time: 10:57 AM
 *   File: SinglyLinkedList.java
 */

package feb08_21_NK.LinkedList;

public class SinglyLinkedList {
    Node head;

    public SinglyLinkedList() {
        head = null;
    }

    public void insertAtBegin(Node newNode) {
        newNode.next = head;
        head = newNode;
    }

    public void printSinglyLinkedList() {
        Node temp = head;
        if (temp == null) {
            System.out.println("No data member");
        } else {
            while (temp != null) {
                System.out.print(temp.data + " -> ");
                temp = temp.next;
            }
            System.out.println();
        }
    }

    public void insertAtEnd(Node newNode) {
        if (head == null) {
            head = newNode;
            return;
        }
        Node temp = head;
        while (temp.next != null) {
            temp = temp.next;
        }
        temp.next = newNode;
        return;
    }

}

The problem with is code is that when you insert the n1 at the last the value is 44 and next is null for this node

but when you insert the same record at the beginning then you modify the value of the next

this is the reason it produce infinity

and there is not loop termination condition