public class IntNode {
    private int data;          // (1)
    private IntNode next;      // (2)
    
    /*
      An integer node, to be used in a list of integers (see IntList)
      (1) contains integer data
      (2) the next IntNode in the list (or null)
    */

    public IntNode(){
	data = -999;
	next = null;
    }
    //
    // The default constructor, producing an empty IntNode element
    //

    public IntNode(int data){
	this.data = data;
	next = null;
    }
    //
    // Another constructor, to produce an IntNode
    // with just data in it (i.e. no reference a next IntNode)
    // You might think of this as "end of the line"
    //

    public IntNode(int data, IntNode next){
	this.data = data;
	this.next = next;
    }
    //
    // Another constructor, to produce an IntNode
    // with data in it, and a reference to another IntNode
    //

    public void setData(int newData){data = newData;}
    //
    // upd8 the data in an IntNode
    //

    public void setNext(IntNode newNext){next = newNext;}
    //
    // upd8 the reference to the next IntNode
    //

    public int getData(){return data;}
    //
    // get the data in the IntNode
    //

    public IntNode getNext(){return next;}

    public String toString(){
	if (next == null)
	    return data + "";
	else 
	    return data + "," + next.toString();
    }

    public static void main(String[] args) throws Exception {
	
	// incase you want to see how it goes, java IntNode

	IntNode x = new IntNode(),
	        y = new IntNode(2),
	        z = new IntNode(1,y);
	System.out.println(x);
	System.out.println(y);
	System.out.println(z);

    }
}