class Test {
  public static void main(String[] args){
    LinkedList xs = new LinkedList();
    xs.add(new Byte(0)); xs.add(new Byte(0));
    Byte x = (Byte) xs.iterator().next();

    LinkedList ys = new LinkedList();
    ys.add("zero"); ys.add("one");
    String y = (String) ys.iterator().next();

    LinkedList zss = new LinkedList();
    zss.add(ys);
    String z = (String)((LinkedList)zss.iterator().next()).iterator().next();

    Byte w = (Byte) ys.iterator().next(); // runtime-exception
  }
}