Here is an alternative syntax for dealing with times. It uses the new
WISE command <code> available</code> instead of the awkward
conctruction I first proposed. I've included sample output.
<p>
You may implement either the original
version or this one. If you have not yet started the other version (or
if you have and what you've written is ugly or incomplete) consider
starting over again with this one.

<pre>
  > java WISE <a href = "courses.txt">courses.txt</a> <a href = "students.txt">students.txt</a> <a href = "professors.txt">professors.txt</a>
  Welcome to Ethan Bolker's WISE implementation.
  WISE> available courses TTh 4     # open courses at specified time
  cs420
  ma141
  WISE> available professors TTh 4  # professors free at specified time	
  Ricardo.Menard
  fred
  WISE> available studentname|ID   # times free for specified student
  MWF 11
  TTh 5
  TTh 7
  WISE> exit
</pre>

The logic for <code> available is</code> 

<pre>
 if the first token after the command is "courses" or "professors"
    the next two tokens specify a TimeOfDay
    print the list of courses or professors at that time
    (just courses with room, just professors without a full schedule)
 else
    the first token after the command is a student name or ID
    print the list of all times that student does not have a course
 else
    error
</pre>