nullprogram.com/blog/2007/10/08/
In preparation for showing off the maze-navigating robot I made last
week, I give you this program I wrote last year.
When I started to learn Java, I wrote this little program for
practice. It features a GUI and multi-threading. It generates a maze
and then slowly solves the maze so you can watch it go. I wrote this
with the GNU project’s Java implementation (never used the official Sun
one). The Makefile is therefore set up for gcj and
gij. The Makefile can build the byte-compiled
.jar file as well as a natively compiled version.
I have updated it to use Ant, and I also use Sun’s OpenJDK these days.
The maze generation algorithm is what I believe to be called the
“straw man” algorithm: the maze starts as a matrix of individual
cells. Break down the walls between two cells that aren’t already
connected and move into it. Choose another wall at random and
repeat. If there are no walls left to break down, go back a
step. Lather, rinse, repeat. If you are back in the starting cell with
no more walls to break down, you are done.
Solving the maze is done in a similar way to generation. Go forward,
right, or left if you can. If not, go back to the previous cell. This
is the same algorithm I employed in the maze-navigating robot I built,
which has kept me pretty busy. I will post pictures of it later.
You can specify the maze height, width, and cell pixel size on the
command line when you run it. This runs with the defaults,
Or if you grabbed the source,
And, for a tiny 100 by 100 maze,
java -jar RunMaze.jar 100 100 5
where,
java -jar RunMaze.jar <width> <height> <cell-size>
So, why learn Java? I still don’t like Java, but I had missed out on
an interesting research opportunity because I had zero Java
experience. I probably wouldn’t use it on my own for anything but
practice, as my own projects don’t really need to be super-portable.
Java is ugly, bulky, and slow, but I don’t want to miss any more
opportunities. Right after I was turned down because of my lack of
experience, I bought a Java textbook and read it cover to cover on
vacation. More importantly, I wrote simple little Java programs (like
the one presented here) as I learned core concepts.
Update 2009-07-07: I use Java all the time at work now. There is
really no escaping it. Except maybe with something like
Clojure …