Plug-in Attributes allow you to include specialised calculations as derived attributes within a RippleDown Knowledge Base. Typical uses are:

  • to encode a calculation that is too complex to be expressed as a Calculated Value Attribute
  • to make use of a proprietary algorithm, e.g. a Risk Calculator or a machine-learning expert system algorithm
  • to make a method call on a remote web server
  • to query a database for more information to add to the case

The steps involved in creating and integrating a Plug-in Attribute are:

  1. Develop the algorithm in Java.
  2. Provide a single Java class containing the method to be called to evaluate the algorithm.
  3. You can provide several methods in the one class if variants of the algorithm can be used. For example, a bone fracture Risk Calculator algorithm may have one method giving the risk of a hip fracture and another giving the risk of any fracture.
  4. Package the Java class in a jar file (see PKS for details).
  5. Place the jar file in the RippleDown server’s plugin folder, /plugins, under the installation folder.
  6. Using the Knowledge Builder’s Attribute Editor, create a Plug-in Attribute referring to this jar file.
  7. Pick the specific method to be used for this Plug-in Attribute. The parameters required for that method will be shown.
  8. Assign an attribute to each parameter required by the algorithm. The corresponding case values will be passed to the algorithm for its evaluation.
  9. The Plug-in Attribute can now be used in rule conditions, or used to define further Calculated Value Attributes.

For assistance in producing Plug-in Attributes, please contact PKS.