jcel is a reasoner for the description logic EL+.
Main features:

• is an OWL 2 EL reasoner (albeit currently with some limitations)
• uses the OWL API 3.2.4
• can be used in Protégé 4.1
• is open source and is available under the LGPL License
• is fully implemented in Java and therefore runs on any operating system
• evaluated by the SEALS Community having the lowest Average Reasoning Time in 2010