catch(NoSuchElementException e)
catch(java.util.NoSuchElementException ex)
	public void clear()	{		// clear all empty rooms		Room next;		for(Enumeration e = m_rooms.elements(); e.hasMoreElements();)		{			try			{				// exception handling is necessary because				// nextElement() will throw a NoSuchElementException				// if no more elements exist and the cast could fail				// and throw a ClassCastException				next = (Room)e.nextElement();			}			catch(ClassCastException e)			{				// ignore the error and continue				continue;			}			catch(NoSuchElementException e)			{				// ignore the error and continue				continue;			}			// check if room is empty or not by using the			// users() function from Room			Enumeration to_check = next.users();			if(!to_check.hasMoreElements())			{				// delete the room				del(next.getName());			}		}	}