private void makeGroups(File groupFile) {
			Scanner s = makeScanner(groupFile);
			String groupName;
			ArrayList<Integer> channels = new ArrayList<Integer>();
			while (s.hasNext()) { // checks to see there is a token in the input
				groupName = s.next(); // next() gets the next token
				while (s.hasNextInt()) {
					channels.add(s.nextInt());
				}
				GroupList.add(new Group(groupName, channels));
				channels.clear(); // empty list for next iteration
			}
			s.close(); // scanner must be closed to signal it's okay to
						// close its underlying stream
			checkForMissingChannels();
		}