/*
 * NOTE for hw3:
 * 
 * Since the interface "nodeInterface" in hw2
 * is different from the interface "nodeInt" in hw3,
 * the "readFromFile" program from hw2 must
 * be slightly modified.  If you figured it
 * out, fine.  Otherwise, here is the revised
 * version (meant for Unix/Linux).  You can
 * do the obvious changes to get this to work
 * for Windows.
 */

  //==================================================
  // readFromFile( fn ) : constructs a list from a file "fn"
  //==================================================
  public int readFromFile(String fn)
    // returns the number of nodes in list
    // the first node in the read-in list is "this"
    // if the returned value is <0, error in opening files
  {
	FileInputStream is = null;
	DataInputStream dis = null;

	try {
		is = new FileInputStream(fn);
	  	dis = new DataInputStream(is); 
	} catch (Exception e) {
		System.out.println("Fail to Open");
	  	return -1;
	}

	int count = 0;
	nodeInt curr = new myNode();
	nodeInt last = this;

	if (curr.readString(dis) < 0) 
	{ return -1;
	} else
	{ ++count;
	  last.setItem(curr.getItem());
	  curr = new nodeInt();
	  while (curr.readString(dis) >= 0)  // allow 0 length item
	  { last.setNext(curr);
	    last = last.getNext();
	    curr = new nodeInt();
	    ++count;
	  }
	}
	return count;
  } //readFromFile