org.corpus-tools.pepper
· A highly extensible plattform for conversion and manipulation of linguistic data between an unbound set of formats. Pepper can be used stand-alone as a command line interface, or be integrated as an API into other software products.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window pepper-3.6.1.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.