Installation:

- Download the package.
- Extract the files:
gzip -d < Rex.tar.gz | tar xvf -
- The directory tree containing the package classes will be created.
Also there will be a testing program called rx.
It is a shell script and for it to work properly in your environment
you should make JAVA and CLASSPATH variables inside the
script point to the appropriate locations on your system.

Running the Test:

- at your shell prompt type:
./rx regexp filename
An alternative invocation performs a specific test known as Khadafy.
It's distributed as part of GNU grep and I found it quite useful.
To run it you should type:
./rx -test khadafy.inp

Terms of Use:

The package is distributed under the terms of the GNU Library General Public Lisense.

Regular Expression Package Documentation
Download Rex(Java Regular Expressions)
Download the Source Code

The author can be reached at sts@noir.crocodile.org