Execution unit (XU)

The execution unit (XU) is a resource adapter for Jakarta EE Connector Architecture (JCA) 2.1. The XU handles the low-level aspects of ruleset execution and collaborates with the server to manage resources.

The XU communicates with the decision engine 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 application server or application client calls the XU to execute rulesets with the engine. Rulesets can share a single XU instance for their execution.

You can modify the behavior of the XU by changing its configuration properties.

For Jakarta 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.