JCLAL: a Java framework for active learning. Active Learning has become an important area of research owing to the increasing number of real-world problems which contain labelled and unlabelled examples at the same time. JCLAL is a Java Class Library for Active Learning which has an architecture that follows strong principles of object-oriented design. It is easy to use, and it allows the developers to adapt, modify and extend the framework according to their needs. The library offers a variety of active learning methods that have been proposed in the literature. The software is available under the GPL license.