public   class  myLinkedList
{

      public  myLinkedList(){}


       public  myLinkedList(Object item)
	  {
	      if  (item!= null )
	      start = end = current =  new  ListItem(item);
	       
	  }


       public  myLinkedList(Object [] items)
	  {
          if  (items!= null )
         {
			  for ( int  i =  0 ;i<items.length;i++ )
			 addItem(items[i]);

			 current = start;
         }
	  }


	   public   void  addItem(Object item)
	{

      ListItem newEnd =  new  ListItem(item);

       if (start== null )
         start=end=newEnd;
             else 
		{
		   end.next = newEnd;
             System.out.println("\n end.next (in addItem)= " + end.next); 
		   end = newEnd;

		   System.out.println(" \n end (in addItem)= " + end); 
		
		}
           
   	}

     public  Object getFirst()
	{
       current = start;
	    return  start ==  null  ?  null  : start.item;

	}

     public  Object getNext()
	{

      if (current!= null )
     {
         current = current.next;
     }
     
	     return  current ==  null  ?  null  : current.item;
	}

	 private  ListItem start =  null ;
	 private  ListItem end =  null ;
	 private  ListItem current =  null ;

            private   class  ListItem
            {
	            public  ListItem(Object item) 
              	{
	         	 this .item  = item;
	          	next =  null ;
		}

          public  String toString()
	       {
              return  "\n  item = (" + item + "),  next:  (" +  next + ") ";
	       }
            private  Object item;
            private  ListItem next;
             } 
}

 import  Geometry.*;

 public   class  PolyLine
{
	 public  PolyLine( double  [][] coords) 
	{

      myPoint [] points =  new  myPoint[coords.length];

	   for ( int  i =  0 ;i<coords.length;i++ )
	  {
          points[i]=  new  myPoint(coords[i][ 0 ],coords[i][ 1 ]);

		  polyline =  new  myLinkedList(points);
	  }

	}

      PolyLine(myPoint [] points) 
	{

        polyline =  new  myLinkedList(points);
	}


        public   void  addPoint(myPoint point)
	{
      polyline.addItem(point);
    
	}


        public   void  addPoint( double  x,  double  y)
	{
      polyline.addItem( new  myPoint(x,y));
    
	}

        public  String toString()
	{

         StringBuffer str =  new  StringBuffer("Polyline");
		 myPoint point = (myPoint) polyline.getFirst();

		  while  ( point !=  null )
		 {
			 str.append(" (" + point + ") ");
 		  point = (myPoint) polyline.getNext();
		 }

          return  str.toString();

	}
    
	  private  myLinkedList polyline;
}