NEW: JPlag Webservice
Try out our new JPlag
web service and client.
What is JPlag
JPlag is a system that finds similarities among multiple sets of
source code files. This way it can detect software plagiarism.
JPlag does not merely compare bytes of text, but is aware of
programming language syntax and program structure and hence is robust
against many kinds of attempts to disguise similarities between
plagiarized files. JPlag currently supports Java, C#, C, C++, Scheme,
and natural language text.
JPlag is typically used to detect and thus discourage the
unallowed copying of student exercise programs in programming
education. But in principle it can also be used to detect stolen
software parts among large amounts of source text or modules that have
been duplicated (and only slightly modified). JPlag has already played
a part in several intellectual property cases where it has been
successfully used by expert witnesses.
JPlag has a powerful graphical interface for presenting its
results. See our example.
Use JPlag
The use of JPlag is free, but you must obtain an account. This
requirement is not only necessary to avoid unauthorized use of JPlag
by students, but also to provide the easy and installation-free access
to the software.
Please use the link on the top of this page to apply for the new
JPlag version. You can still apply for the old JPlag version by
contacting the authors at JPlag@ira.uka.de, but you should
expect some delay when creating your account. Shortly describe the
purpose for which you want to use JPlag (which university/school and
course etc.). Please note that we do not give accounts to users of
anonymous email address like Hotmail, Yahoo, Gmail, etc.
Just to make it clear: Currently JPlag does not compare to the
internet! It is designed to find similarities among the student
solutions, which is usually sufficient for computer programs.
Credits: Who, when, why?
JPlag was developed by Guido
Malpohl. In 1996 it started out as a student research project and
a few month later it evolved into the online system you see now. The
author is currently involved in his Ph.D. thesis on a completely
different subject, but is still maintaining and enhancing JPlag.
The server is located at the research group of
Prof. W. Tichy. The group
is a part of the Department of
Informatics at the University of Karlsruhe.
Guido Malpohl