java .lang.ClassCastException: org.primefaces.component.column.Column нельзя преобразовать в org.primefaces.component.row.Row

Question

Я пытаюсь выполнить поиск данных по таблице. Я попытался следовать примеру в витрине простых символов для фильтра DataTable. Однако, как ни странно, когда я ввожу значение, которое я хочу найти, содержимое таблицы будет сразу пустым. Например, я хочу найти имя пользователя «А», тогда, когда я наберу «А», содержимое таблицы исчезнет. Вот мой стол:

<h:form id="dataTable">
    <p:dataTable var="users" rows="10" value="#{listUserAccountBean.users}"
        style="width: 100%; float: left; margin-top:10px;" paginator="true"
        pageLinks="10" rowsPerPageTemplate="5,10,15"
        widgetVar="widgetWorkOrder" rowIndexVar="rowIndex" 
        paginatorPosition="bottom" emptyMessage="No record found" 
        styleClass="no-dtbl-header" id="listDataUser" filteredValue="#{listUserAccountBean.filteredUsers}"
        paginatorTemplate="{CurrentPageReport}  {FirstPageLink} {PreviousPageLink} {PageLinks}  {NextPageLink}  {LastPageLink}  {RowsPerPageDropdown}">

        <f:facet name="header">
            <p:outputPanel>
                <h:outputText value="Search all fields:" />
                <p:inputText id="globalFilter" onkeyup="PF('widgetWorkOrder').filter()" placeholder="Enter keyword"/>
            </p:outputPanel>
        </f:facet>

        <p:columnGroup type="header">
            <p:column headerText="Username" />
            <p:column headerText="Password" />
            <p:column headerText="Action" colspan="2"/>
        </p:columnGroup>
        <p:column filterBy="#{users.username}" footerText="test1" filterMatchMode="test1">
            <h:outputText value="#{users.username}" />
        </p:column>
        <p:column filterBy="#{users.password}" footerText="test2" filterMatchMode="test2">
            <h:outputText value="#{users.password}" />
        </p:column>
        <p:column style="text-align: center">
            <p:commandLink action="#{listUserAccountBean.goToEditUserAccount(users)}">
                <p:graphicImage name="edit.png" library="images" width="25px"
                    height="25px" />
            </p:commandLink>
        </p:column>
        <p:column style="text-align: center">
            <p:commandLink actionListener="#{listUserAccountBean.prepareDelete(users)}"
                oncomplete="PF('dlg-delete').show();">
                <p:graphicImage name="delete-admin.png" library="images"
                    width="25px" height="25px" />
            </p:commandLink>
        </p:column>
    </p:dataTable>
</h:form>

Вот мой журнал кошек:

14:37:38,073 INFO  [javax.enterprise.resource.webcontainer.jsf.context] (http-localhost-127.0.0.1-8081-2) java.lang.ClassCastException: org.primefaces.component.column.Column cannot be cast to org.primefaces.component.row.Row: java.lang.ClassCastException: org.primefaces.component.column.Column cannot be cast to org.primefaces.component.row.Row
at org.primefaces.component.datatable.feature.FilterFeature.populateFilterMetaDataInColumnGroup(FilterFeature.java:283) [primefaces-5.3.jar:5.3]
at org.primefaces.component.datatable.feature.FilterFeature.populateFilterMetaData(FilterFeature.java:257) [primefaces-5.3.jar:5.3]
at org.primefaces.component.datatable.feature.FilterFeature.decode(FilterFeature.java:90) [primefaces-5.3.jar:5.3]
at org.primefaces.component.datatable.DataTable.processValidators(DataTable.java:716) [primefaces-5.3.jar:5.3]
at com.sun.faces.context.PartialViewContextImpl$PhaseAwareVisitCallback.visit(PartialViewContextImpl.java:508) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.component.visit.PartialVisitContext.invokeVisitCallback(PartialVisitContext.java:183) [jsf-impl-2.1.7-jbossorg-2.jar:]
at org.primefaces.component.api.UIData.visitTree(UIData.java:822) [primefaces-5.3.jar:5.3]
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIForm.visitTree(UIForm.java:371) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.visitTree(UIComponent.java:1623) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.context.PartialViewContextImpl.processComponents(PartialViewContextImpl.java:376) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.context.PartialViewContextImpl.processPartial(PartialViewContextImpl.java:252) [jsf-impl-2.1.7-jbossorg-2.jar:]
at org.primefaces.context.PrimePartialViewContext.processPartial(PrimePartialViewContext.java:60) [primefaces-5.3.jar:5.3]
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1170) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:593) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:329) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
at org.apache.logging.log4j.web.Log4jServletFilter.doFilter(Log4jServletFilter.java:67) [log4j-web-2.0.2.jar:2.0.2]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:280) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:248) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:275) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:161) [jbossweb-7.0.13.Final.jar:]
at org.jboss.as.web.security.SecurityContextAssociationValve.invoke(SecurityContextAssociationValve.java:153) [jboss-as-web-7.1.1.Final.jar:7.1.1.Final]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) [jbossweb-7.0.13.Final.jar:]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:368) [jbossweb-7.0.13.Final.jar:]
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:877) [jbossweb-7.0.13.Final.jar:]
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:671) [jbossweb-7.0.13.Final.jar:]
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:930) [jbossweb-7.0.13.Final.jar:]
at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_21]

14:37:38,020 SEVERE [javax.enterprise.resource.webcontainer.jsf.context] (http-localhost-127.0.0.1-8081-2) java.lang.NullPointerException

Я что-то пропустил?