Ajax Framework - Listener

A java method can be invoked in an ajax request using listener option of p:ajax.

Keyup:
<h:form>
    <h:panelGrid columns="3">
        <h:outputText value="Keyup: " />
        <p:inputText id="counter" value="#{listenerView.text}">
            <p:ajax event="keyup" update="out" listener="#{listenerView.handleKeyEvent}" />
        </p:inputText>
        <h:outputText id="out" value="#{listenerView.text}" />
    </h:panelGrid>
</h:form>