CHSM (Concurrent Hierarchical State Machine) is a Statecharts
    implementation for C++ and Java that allows one to integrate
    state definitions, event handlers, and transitions seamlessly
    into the host language's object model.

    CHSM allows normal Java or C++ code to be intermixed with the
    Statechart definition promoting a clear and natural programming
    paradigm.  The CHSM is a full implementation of Harel's
    Statecharts and it is compliant with the UML 2.0 specification,
    including mechanisms for Statechart inheritance, event
    inheritance, and generic event dispatching.

    The CHSM system includes compilers for translating the CHSM
    Statecharts language to either C++ or Java, as well as a run-
    time library to support Statechart execution semantics.  The
    generated code and the run-time libraries have been designed
    for safety, efficiency and small footprint size, making it an
    ideal choice for embedded systems, control systems, user
    interfaces, communication protocols, and web service
    applications.

    The CHSM run-time implements the Statechart's Micro Step
    execution semantics that ensures safety and liveness properties
    to state machine specifications, a critical feature for many
    embedded and real-time applications.

    CHSM is distributed as open source software under the GNU
    Public Licensing scheme, although commercial licenses might be
    negotiated with the authors.

    CHSM has a homepage:

        http://homepage.mac.com/pauljlucas/software/chsm/

    - Paul