Working with Events

The Business Components for Java framework follows the standard Java/EJB event delegation model for propagating events among middle-tier objects. Publishers (also called senders) fire events, subscribers (also called listeners) respond to them.

Java event types are classes that extend java.util.EventObject. The framework sends an event from a publisher to a subscriber by invoking a method of the RowSetListener interface on the subscriber and passing in an instance of the event type generated. The subscriber registers listeners by using addEventTypeListener() on the publisher.

The publisher defines the set of events it emits by providing addEventTypeListener methods which register specific listeners for those events.

A subscriber implements a specific EventListener interface, RowSetListener, that extends java.util.EventListener. An EventListener interface defines one or more methods to invoke in response to each specific event type handled by the interface.