Simple LinkedList

public class LinkedList {
    
    private Node head;
  
    public static void main(String[] args) {
      LinkedList ll = new LinkedList();
      ll.add(1);
      ll.add(2);
      ll.add(3);
      ll.add(4);
      
      ll.print();
      
      ll.delete(1);
      ll.print();
      
      ll.delete(3);
      ll.print();
      
      
//      ll.delete(4);      
//      ll.print();
    }
    
    public void add(int data) {
      if (head == null) {
        head= new Node(data, null);
        
        return;
      }
      
      // Go to the end of the list.
      Node currentLastNode = head;
      while (currentLastNode.next != null) {
        currentLastNode = currentLastNode.next;
      }
      
      Node newLastNode = new Node(data, null);
      
      currentLastNode.next = newLastNode;
    }
    
    public boolean delete(int dataToDelete) {
      Node currentNode = head;
      Node previousNode = null;
      
      while(currentNode != null) {
        if (currentNode.data == dataToDelete){
          if (previousNode != null)    {
            previousNode.next = currentNode.next; 
          } 
          else  {
            // delete first node
            head = currentNode.next;
          }
          
          return true;
        } 
        else {
        	previousNode = currentNode;
        	currentNode = currentNode.next;
        }
      } 
      
      return false;
    }  
    
    public void print() {
      Node tmp = head;
      
      while(tmp != null) {
        System.out.print(tmp.data + "->");
        
        tmp = tmp.next;
      }
      System.out.println();
    }  
    
    class Node {
      public int data;
      public Node next;
      
      Node(int data, Node next) {
        this.data = data;
        this.next = next;
      }  
    }  
}