This figure demonstrates how when all data tokens are available and the conditions are matched, the reaction fires, which causes the method to execute.

The figure shows that a reaction pulls three data tokens from the AC4J data bus. If these data tokens match the reaction conditions (for example, constraint on the values of a data token), then the reaction fires. The firing of a reaction executes the Active EJB method and may generate one or more data tokens. These data tokens can be for the return values to the called process or for more requests for one or more Active EJBs.