You should really get clarification from Professor Slonneger
Also, you should have noted in your syllabus:
Policies

1) You are encouraged to discuss the course material with other students,but
all written work and programming projects must be your work alone.The grader
will be looking for similarities in assignment submissions.

2) The Departmental policy with regard to cheating suggests a penalty
between a zero on the assignment and an F in the course for a first offense.
A second offense will result in a penalty between an F in the course and a
recommendation of expulsion to the Dean of the College. The full policy on
academic misconduct is on-line in the College's Student Academic Handbook

 I'd give you 2 points for acknowledging that this is a HW problem and
asking for direction rather than asking for anyone to solve the problem
for you!

Anyway, first you should try to clarify this with the teacher, he's the
only one that really matters, you need to understand what he is looking
for. When you talk to him I would also talk to him about posting to
newsgroups. Some teachers will realize that used correctly it is a
resource to help you learn, some don't. Find out his stance, you don't
know if he visits here! And if something comes of it, it is better to be
open early before you come to finals and then he raises a stink.

If I get your question right, you don't understand why he is asking for
multiple files. Think of it this way. Except for very simple programs
you never throw everything into one method. Instead, you write multiple
methods that do one thing well, this eliminates redundant code. You do
the same thing with multiple class/files. Ex. ParseWren.java should be
passed exactly what he describes and should return exactly what he
describes. It should not contain anything to print the output, thats
handled in ParseDriver.java.