Hola amigos foristas mi problema es cuando ejecuto una simple aplicacion con dos combos (select multiples) donde tambien estoy trabajando con la libreria ajax4jsf, lo mas extraño es que con el ejemplo original el cual me guie funciona bien y descarto qe sean problema de incompatibiliad de librerias con el JSF 1.1,quizas a algunos les ha pasado esto ya que buscando en google encontraba problemas similares.
Debugenado mi aplicacion si logro cargar mis datos dentro de los backingbean para los combos ,pero no los muestra en la pagina
<h:panelGrid columns="2">
<h:outputText value="Tipo Usuario"/>
<h:selectOneMenu valueChangeListener="#{usuarioBean.seleccionarTipo }" >
<f:selectItems value="#{usuarioBean.itemstipouser}"/>
<a4j:support event="onchange" reRender="seluser" />
</h:selectOneMenu>
<h:outputText value="Nombre y Apellidos"/>
<h:selectOneMenu id="seluser" valueChangeListener="#{usuarioBean.seleccionarUsua rio}" >
<f:selectItems value="#{usuarioBean.itemsusuarios}"/>
<a4j:support event="onchange" reRender="datos" />
</h:selectOneMenu>
</h:panelGrid>
<h:outputText id="datos" value="#{usuarioBean.resultado}"/>
</h:form>
Este es el error que me arroja:
29-jun-2009 14:37:16 com.sun.faces.lifecycle.LifecycleImpl phase
ADVERTENCIA: executePhase(RENDER_RESPONSE 6,com.sun.faces.context.FacesContextImpl@fccada) threw exception
java.lang.NullPointerException
at java.io.PrintWriter.write(Unknown Source)
at com.sun.faces.application.ViewHandlerImpl$WriteBeh indStateWriter.write(ViewHandlerImpl.java:834)
at com.sun.faces.renderkit.html_basic.HtmlResponseWri ter.write(HtmlResponseWriter.java:495)
at com.sun.faces.renderkit.html_basic.MenuRenderer.re nderOption(MenuRenderer.java:584)
at com.sun.faces.renderkit.html_basic.MenuRenderer.re nderOptions(MenuRenderer.java:757)
at com.sun.faces.renderkit.html_basic.MenuRenderer.re nderSelect(MenuRenderer.java:811)
at com.sun.faces.renderkit.html_basic.MenuRenderer.en codeEnd(MenuRenderer.java:335)
at javax.faces.component.UIComponentBase.encodeEnd(UI ComponentBase.java:833)
at com.sun.faces.renderkit.html_basic.HtmlBasicRender er.encodeRecursive(HtmlBasicRenderer.java:279)
at com.sun.faces.renderkit.html_basic.GridRenderer.en codeChildren(GridRenderer.java:242)
at javax.faces.component.UIComponentBase.encodeChildr en(UIComponentBase.java:809)
at javax.faces.component.UIComponent.encodeAll(UIComp onent.java:886)
at javax.faces.render.Renderer.encodeChildren(Rendere r.java:137)
at javax.faces.component.UIComponentBase.encodeChildr en(UIComponentBase.java:809)
at javax.faces.component.UIComponent.encodeAll(UIComp onent.java:886)
at javax.faces.component.UIComponent.encodeAll(UIComp onent.java:892)
at com.sun.faces.application.ViewHandlerImpl.doRender View(ViewHandlerImpl.java:245)
at com.sun.faces.application.ViewHandlerImpl.renderVi ew(ViewHandlerImpl.java:176)
at org.ajax4jsf.framework.ViewHandlerWrapper.renderVi ew(ViewHandlerWrapper.java:108)
at org.ajax4jsf.framework.ajax.AjaxViewHandler.render View(AjaxViewHandler.java:233)
at com.sun.faces.lifecycle.RenderResponsePhase.execut e(RenderResponsePhase.java:106)
at com.sun.faces.lifecycle.LifecycleImpl.phase(Lifecy cleImpl.java:251)
at com.sun.faces.lifecycle.LifecycleImpl.render(Lifec ycleImpl.java:144)
at javax.faces.webapp.FacesServlet.service(FacesServl et.java:245)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:206)
at org.ajax4jsf.framework.ajax.xmlfilter.BaseXMLFilte r.doXmlFilter(BaseXMLFilter.java:127)
at org.ajax4jsf.framework.ajax.xmlfilter.BaseFilter.d oFilter(BaseFilter.java:277)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invo ke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invo ke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke( StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke (ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invok e(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.servic e(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(H ttp11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11Conn ectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run( JIoEndpoint.java:447)
at java.lang.Thread.run(Unknown Source)
29-jun-2009 14:37:16 org.apache.catalina.core.StandardWrapperValve invoke
GRAVE: Servlet.service() para servlet Faces Servlet lanz� excepci�n
java.lang.NullPointerException
at java.io.PrintWriter.write(Unknown Source)
at com.sun.faces.application.ViewHandlerImpl$WriteBeh indStateWriter.write(ViewHandlerImpl.java:834)
at com.sun.faces.renderkit.html_basic.HtmlResponseWri ter.write(HtmlResponseWriter.java:495)
at com.sun.faces.renderkit.html_basic.MenuRenderer.re nderOption(MenuRenderer.java:584)
at com.sun.faces.renderkit.html_basic.MenuRenderer.re nderOptions(MenuRenderer.java:757)
at com.sun.faces.renderkit.html_basic.MenuRenderer.re nderSelect(MenuRenderer.java:811)
at com.sun.faces.renderkit.html_basic.MenuRenderer.en codeEnd(MenuRenderer.java:335)
at javax.faces.component.UIComponentBase.encodeEnd(UI ComponentBase.java:833)
at com.sun.faces.renderkit.html_basic.HtmlBasicRender er.encodeRecursive(HtmlBasicRenderer.java:279)
at com.sun.faces.renderkit.html_basic.GridRenderer.en codeChildren(GridRenderer.java:242)
at javax.faces.component.UIComponentBase.encodeChildr en(UIComponentBase.java:809)
at javax.faces.component.UIComponent.encodeAll(UIComp onent.java:886)
at javax.faces.render.Renderer.encodeChildren(Rendere r.java:137)
at javax.faces.component.UIComponentBase.encodeChildr en(UIComponentBase.java:809)
at javax.faces.component.UIComponent.encodeAll(UIComp onent.java:886)
at javax.faces.component.UIComponent.encodeAll(UIComp onent.java:892)
at com.sun.faces.application.ViewHandlerImpl.doRender View(ViewHandlerImpl.java:245)
at com.sun.faces.application.ViewHandlerImpl.renderVi ew(ViewHandlerImpl.java:176)
at org.ajax4jsf.framework.ViewHandlerWrapper.renderVi ew(ViewHandlerWrapper.java:108)
at org.ajax4jsf.framework.ajax.AjaxViewHandler.render View(AjaxViewHandler.java:233)
at com.sun.faces.lifecycle.RenderResponsePhase.execut e(RenderResponsePhase.java:106)
at com.sun.faces.lifecycle.LifecycleImpl.phase(Lifecy cleImpl.java:251)
at com.sun.faces.lifecycle.LifecycleImpl.render(Lifec ycleImpl.java:144)
at javax.faces.webapp.FacesServlet.service(FacesServl et.java:245)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:206)
at org.ajax4jsf.framework.ajax.xmlfilter.BaseXMLFilte r.doXmlFilter(BaseXMLFilter.java:127)
at org.ajax4jsf.framework.ajax.xmlfilter.BaseFilter.d oFilter(BaseFilter.java:277)
at org.apache.catalina.core.ApplicationFilterChain.in ternalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.do Filter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invo ke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invo ke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke( StandardHostValve.java:128)
at org.apache.catalina.valves.ErrorReportValve.invoke (ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invok e(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.servic e(CoyoteAdapter.java:286)
at org.apache.coyote.http11.Http11Processor.process(H ttp11Processor.java:845)
at org.apache.coyote.http11.Http11Protocol$Http11Conn ectionHandler.process(Http11Protocol.java:583)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run( JIoEndpoint.java:447)
at java.lang.Thread.run(Unknown Source)
Necesito su Ayuda porfavor..
Gracias de antemano
Respuesta: Problema con JSF (select multiple) 
