PDDL4J is an open source library under licence CECILL (http://www.cecill.info/). The purpose of the PDDL4J is to facilitate the java implementation of planners based on the PDDL (Planning Description Language). The library contains a parser on the last version of PDDL 3.0 and all the classes need to manipulate its concepts. The parser can be configured to accept only specified requirements of PDDL langage. The list of requirements accepted are as follow:
PDDL was originally developed by Drew McDermott and the 1998 planning competition committee. It was inspired by the need to encourage the empirical comparison of planning systems and the exchange of planning benchmarks within the community. Its development improved the communication of research results and triggered an explosion in performance, expressivity and robustness of planning systems.
PDDL has now been used in all 3 planning competitions, undergoing various revisions for each. In the most recent competition PDDL was extended by Maria Fox, Derek Long and the 2002 committee to handle time and duration (PDDL2.1). Further enrichments to the modelling of hybrid and real-time systems (PDDL+) were proposed, while another committee is currently investigating extensions to probabilistic planning.
PDDL has become a de facto standard language for describing planning domains, not only for the competition but more widely, as it offers an opportunity to carry out empirical evaluation of planning systems on a growing collection of generally adopted standard benchmark domains. The emergence of a language standard will have an impact on the entire field, influencing what is seen as central and what peripheral in the development of planning systems.