5.3. <a4j:actionListener>

Use the <a4j:actionListener> tag to register an ActionListener class on a parent action component. The class provided as a listener must implement the javax.faces.event.ActionListener interface. Multiple listener methods can be registered on an action component in this way.
The <a4j:actionListener> tag differs from the standard JSF tag by allowing a listener method to be defined instead of just a class. Use the listener attribute to define the listener method.