catch(ClassCastException e) { return null; }
	public Room room(String name)	{		// return the room with the name in the variable name		// if this room does not exist this container will create		// a new object, put it into the m_rooms hashtable and		// return it.		Room to_ret;		try		{			// exception handling is necessary because			// get() and put() will throw a			// NullPointerException if the key is null.			to_ret = m_rooms.get(name);			// if this room does not exist, create			// a new room.			if(to_ret == null)			{				to_ret = new RoomImpl(name);				m_rooms.put(name, to_ret);			}			return to_ret;		}		catch(NullPointerException e)		{			return null;		}	}