This program was originally written as a project for a cryptography class I was taking in college. Specifically, I wrote it to help me complete the assignments for the class which consited largely of having to break various classical ciphers as they were introduced in class, along with techniques for effectively cryptoanalyzing the ciphers.
You can download the latest release of this program from sourceforge here.
You can look at screenshots of the program here.
This program is licensed under the GPL and the sourcecode can be accessed via anonymous CVS through sourceforge. The sourcecode is also located in the *.jar distrobution file. If you UnZip the *.jar archive you can acess all the class files as well as the sourcefiles.
You can access the sourcecode via anonymous SVN with the following commands (assuming that the svn command is installed and it is included in your PATH environment variable.)
svn co https://svn.sourceforge.net/svnroot/cryptohelper
This command will create a directory called cryptohelper which will have all the latest source code in it.
This program was written using the netbeans IDE for the java programming language. It would be useful although not absolutely necessary for any future work on this project to be done using that IDE.