Teaching CP systems in Java using Gecode/J

A course covering constraint programming (CP) systems should include at least four main topics: modeling, propagators (implementing constraints), branchings (non-deterministic choice), and exploration of the search tree. In order to de-liver a hands-on experience to the students, we have developed Gecode/J [2], a Java interface to the Gecode C++ library [3]. Using Gecode/J, students can get acquainted with all four aforementioned topics in a programming language they are familiar with. Both Gecode and Gecode/J are open source software. The full source code, an API reference and some example programs are available from the project web pages. Gecode/J has been used for teaching CP courses at KTH and at Uppsala University in Sweden, and at Universite ́ Catholique de Louvain in Belgium. The Gecode constraint programming library is designed to enable the imple-mentation of highly efficient components. This, necessarily, exposes quite some complexity to the user. For teaching, a less complex system at a higher level of abstraction is desirable