Execution unit (XU)
The execution unit (XU) is a resource adapter for Java™ EE Connector Architecture (JCA) 1.5. The XU handles the low-level aspects of ruleset execution and collaborates with the server to manage resources.
The XU communicates with the rule engines and collaborates with the resource adapter container. It manages resources through services such as work management, connection management, lifecycle management, and resource adapter configuration.
The XU supports both rule engines: the classic rule engine or the decision engine.
The application server or application client calls the XU to execute rulesets with the engine.
Rulesets for use with the classic rule engine and rulesets for use with the decision engine can share a single XU instance for their execution.
The classic
rule engine is deprecated in V8.9.0. This feature will be removed
in a future release of the product. See Deprecated features for migration
details.
- For Java EE sessions, the configuration properties of the XU are defined in the META-INF/ra.xml file of the .RAR artifact.
- For Java SE sessions, you can change the configuration properties of the XU by API or by adding a configuration file in the application class path. Pass the XU configuration during the initialization of the session factory. You cannot change the configuration of the XU after the factory is initialized.