Description of problem:

A composite component with ClientBehavior targeting containing a commandbutton produces a nullpointer exception when the button is clicked.

10:19:15,003 WARNING [javax.enterprise.resource.webcontainer.jsf.lifecycle] (http-/127.0.0.1:8080-1) #{clientBehavior1Bean.action}: java.lang.NullPointerException: javax.faces.FacesException: #{clientBehavior1Bean.action}: java.lang.NullPointerException
	at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:109) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	at javax.faces.component.UICommand.broadcast(UICommand.java:315) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	at javax.faces.component.UIViewRoot.broadcastEvents(UIViewRoot.java:786) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	at javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:1251) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	at com.sun.faces.lifecycle.InvokeApplicationPhase.execute(InvokeApplicationPhase.java:81) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:295) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:231) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:149) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:169) [jboss-as-web-7.5.6.Final-redhat-2.jar:7.5.6.Final-redhat-2]
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:150) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:97) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:102) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:854) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:653) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:926) [jbossweb-7.5.12.Final-redhat-1.jar:7.5.12.Final-redhat-1]
	at java.lang.Thread.run(Thread.java:745) [rt.jar:1.8.0_65]
Caused by: javax.faces.el.MethodNotFoundException: java.lang.NullPointerException
	at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:103) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	at com.sun.faces.application.ActionListenerImpl.processAction(ActionListenerImpl.java:101) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	... 20 more
Caused by: java.lang.NullPointerException
	at javax.faces.component.UIComponentBase.findComponent(UIComponentBase.java:563) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	at com.sun.faces.facelets.el.ContextualCompositeMethodExpression.pushCompositeComponent(ContextualCompositeMethodExpression.java:304) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	at com.sun.faces.facelets.el.ContextualCompositeMethodExpression.invoke(ContextualCompositeMethodExpression.java:190) [jsf-impl-2.1.28.redhat-10.jar:2.1.28.redhat-10]
	at javax.faces.component.MethodBindingMethodExpressionAdapter.invoke(MethodBindingMethodExpressionAdapter.java:87) [jboss-jsf-api_2.1_spec-2.1.28.SP1-redhat-1.jar:2.1.28.SP1-redhat-1]
	... 21 more

Version-Release number of selected component (if applicable):

2.1.28.SP1

How reproducible:

A composite component with ClientBehavior targeting containing a command-button produces a nullpointer exception when the button is clicked.

Steps to Reproduce:
a command-button like below produces a nullpointer exception when the button is clicked.

<html xmlns="http://www.w3.org/1999/xhtml"
      xmlns:h="http://java.sun.com/jsf/html"
      xmlns:clientBehavior="http://java.sun.com/jsf/composite/clientBehavior" 
      xmlns:f="http://java.sun.com/jsf/core">
    <f:view transient="true">
        <h:head>
            <title>Simple JSF Facelets page</title>
        </h:head>
        <h:body>
            Place your content here
            <br/>
            <h:form id="exampleForm">
                <h:outputText value="#{clientBehavior1Bean.text}"/>
                <clientBehavior:clientBehavior1 action="#{clientBehavior1Bean.action}" id="customButton">
                    <f:ajax execute="@this" render="@form"/>
                </clientBehavior:clientBehavior1>
            </h:form>
        </h:body>
    </f:view>
</html>

Actual results:


Expected results:


Additional info:

https://java.net/jira/browse/JAVASERVERFACES-3563