It is written entirely in Java. It also makes use of Weka for the actual machine learning.
It is the software Waleed Kadous developed for his PhD on the subject.
More specific information can be found in:
For simplicity, Weka 3.2.3 class files are included in TClass, but you may wish to download Weka 3.2.3 for the documentation or for your own experiments.
jar xvf tclass-1.0.0.jar to uncompress it.