Jess, the Java Expert System Shell - Embedding Jess in a Java Application

6. Embedding Jess in a Java Application

6.1. Using the class jess.Main

The class jess.Main provides not only the Jess command-line interface, but also the backbone of the example graphical interfaces (jess.Console and jess.ConsoleApplet) as well. You can reuse jess.Main from your own applications, or you can simply use it as an example of what an application embedding Jess can look like. jess.Main does a number of things that a reasonable Jess application might do:

It reads the script library jess/scriptlib.clp and installs an event-handler so that the file will be re-read clear() is called.
It (optionally) reads an entire file of Jess code directly, using the jess.Jesp parser class.
It reads and executes user input in a loop.
It provides special handling for the bload and bsave commands, which disrupt the normal flow of execution.

6.2. Manipulating Jess in other ways

Note that each individual jess.Rete object represents an independent reasoning engine. A single program can then include several indepenent engines.

Jess can be used in a multithreaded environment. The jess.Rete class internally synchronizes itself using several synchronization locks. The most important lock is a global lock on all rule LHSs: only one assert or retract may be processing int a given jess.Rete object at a time. This restriction is likely to be relaxed in the future.