Linked list connectin of Slist and SListNode class

See more:

algorithm

I was watching a video on data structures and algorithms offered

There firstly code for linked list was written as

public class SListNode{
    public Object item;
    public SListNode next;
    public SListNode(Object item,SListNode next){
        this.item=item;
        this.next=next; 
    }
    public SListNode(Object item){
        this(item,null);
    }
    public void insertAfter(Object item){
        next=new SListNode(item,next);  
    }
    public SListNode nth(int position){
        if (position==1){
            return this;
        }
        else if ((position<1)|| next==null){
            return null;
        }
        else{
            return next.nth(position-1);
        }

    }

Then the lecturer said that there are two problems associated with this implementation.

1)if X and Y refer to the same list and if a new item was inserted to x , y doesn't get updated.I think this can be checked by

public static void main (String args[]){
        SListNode l1=new SListNode("milk",new SListNode(0,new SListNode(1)));
        SListNode l2=l1;
        l2=new SListNode("soap",l2);
        System.out.println(l1.item+ " "+l1.next.item+ " " +l1.next.next.item);
        System.out.println(l2.item+ " "+l2.next.item+ " " +l2.next.next.item);  

2)when creating an empty list.

Therefore as a solution separate SListClass that maintains head of list was created.

public class SList{
    privte SListNode head;
    private int size;
    public SList(){
        head=null;
        size=0;
    }
    public void insertFront(Object item){
    head=new SListNode(item,head);
    size++;
    }
}

I don't understand how to work with SList class.
How to create a linked list with this class?If I want to create a new linked list with items 34,"a",100 how is this done?Is it done by

SListNode l_0=new SListNode(34,new SListNode("a",new SListNode(100)));

.If so then how is the connection with head in SList is made with this linked list l_0

How is SListNode and Slist classes are connected and how can the methods of SlistNode be called from SList?
Also how has this new implementation provide a solution to earlier problem of if X and Y refer to the same list and if a new item was inserted to x , y doesn't get updated.

I am new to programming and Java therefore a clear explanation would be great