我刚开始使用PrimeFaces 3.3.1，之前使用过RichFaces 3和4。
我的数据表格结构如下：
<f:facet name="header">
<h:outputText value="Employees" />
</f:facet>
<p:column sortBy="#{emp.lastName}">
<f:facet name="header">
<h:outputText value="Last Name" />
</f:facet>
<h:outputText value="#{emp.lastName}" />
</p:column>
<p:column>
<f:facet name="header">
<h:outputText value="First Name" />
</f:facet>
<h:outputText value="#{emp.firstName}" />
</p:column>
...
<p:column>
<p:commandButton icon="ui-icon ui-icon-trash"
value="Remove"
process="@this"
update="employee-remove-dialog"
oncomplete="employeeRemoveDialog.show();">
<f:setPropertyActionListener target="#{employeeManager.currentEmployee}" value="#{emp}" />
</p:commandButton>
</p:column>
</p:dataTable>
<p:dialog header="Remove Employee"
modal="true"
appendToBody="true"
widgetVar="employeeRemoveDialog"
id="employee-remove-dialog">
<h:outputText value="Remove employee #{employeeManager.currentEmployee.fullName}?" />
<f:facet name="footer">
<p:commandButton icon="ui-icon ui-icon-check"
value="OK"
action="#{employeeManager.deleteEmployee}"
process="@this"
update="employee-list"
oncomplete="employeeRemoveDialog.hide();" />
<p:commandButton icon="ui-icon ui-icon-close"
value="Cancel"
onclick="employeeRemoveDialog.hide();"
ajax="false"
immediate="true" />
</f:facet>
</p:dialog>
</h:form>
然而，PrimeFaces抛出了一个例外：
09:36:08,961 SEVERE [javax.enterprise.resource.webcontainer.jsf.application] (http-localhost-127.0.0.1-8080-1) Error Rendering View[/employeeList.xhtml]: javax.faces.FacesException: Cannot find component with identifier "employee-remove-dialog" referenced from "j_idt30:employee-list:0:j_idt41".
at org.primefaces.util.ComponentUtils.findClientIds(ComponentUtils.java:251) [primefaces-3.3.1.jar:]
at org.primefaces.util.AjaxRequestBuilder.addIds(AjaxRequestBuilder.java:102) [primefaces-3.3.1.jar:]
at org.primefaces.util.AjaxRequestBuilder.update(AjaxRequestBuilder.java:90) [primefaces-3.3.1.jar:]
at org.primefaces.renderkit.CoreRenderer.buildAjaxRequest(CoreRenderer.java:195) [primefaces-3.3.1.jar:]
at org.primefaces.component.commandbutton.CommandButtonRenderer.encodeMarkup(CommandButtonRenderer.java:74) [primefaces-3.3.1.jar:]
at org.primefaces.component.commandbutton.CommandButtonRenderer.encodeEnd(CommandButtonRenderer.java:49) [primefaces-3.3.1.jar:]
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.renderkit.html_basic.HtmlBasicRenderer.encodeRecursive(HtmlBasicRenderer.java:312) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.renderkit.html_basic.GridRenderer.renderRow(GridRenderer.java:185) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.renderkit.html_basic.GridRenderer.encodeChildren(GridRenderer.java:129) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1779) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at org.primefaces.component.datatable.DataTableRenderer.encodeRegularCell(DataTableRenderer.java:780) [primefaces-3.3.1.jar:]
at org.primefaces.component.datatable.DataTableRenderer.encodeRow(DataTableRenderer.java:741) [primefaces-3.3.1.jar:]
at org.primefaces.component.datatable.DataTableRenderer.encodeTbody(DataTableRenderer.java:645) [primefaces-3.3.1.jar:]
at org.primefaces.component.datatable.DataTableRenderer.encodeRegularTable(DataTableRenderer.java:248) [primefaces-3.3.1.jar:]
at org.primefaces.component.datatable.DataTableRenderer.encodeMarkup(DataTableRenderer.java:220) [primefaces-3.3.1.jar:]
at org.primefaces.component.datatable.DataTableRenderer.encodeEnd(DataTableRenderer.java:107) [primefaces-3.3.1.jar:]
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1786) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.render.Renderer.encodeChildren(Renderer.java:168) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponentBase.encodeChildren(UIComponentBase.java:845) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at org.primefaces.renderkit.CoreRenderer.renderChild(CoreRenderer.java:55) [primefaces-3.3.1.jar:]
at org.primefaces.renderkit.CoreRenderer.renderChildren(CoreRenderer.java:43) [primefaces-3.3.1.jar:]
at org.primefaces.component.layout.LayoutUnitRenderer.encodeEnd(LayoutUnitRenderer.java:51) [primefaces-3.3.1.jar:]
at javax.faces.component.UIComponentBase.encodeEnd(UIComponentBase.java:875) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1786) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at javax.faces.component.UIComponent.encodeAll(UIComponent.java:1782) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.application.view.FaceletViewHandlingStrategy.renderView(FaceletViewHandlingStrategy.java:402) [jsf-impl-2.1.7-jbossorg-2.jar:]
at com.sun.faces.application.view.MultiViewHandler.renderView(MultiViewHandler.java:125) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.application.ViewHandlerWrapper.renderView(ViewHandlerWrapper.java:288) [jboss-jsf-api_2.1_spec-2.0.1.Final.jar:2.0.1.Final]
at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:121) [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.render(LifecycleImpl.java:139) [jsf-impl-2.1.7-jbossorg-2.jar:]
at javax.faces.webapp.FacesServlet.service(FacesServlet.java:594) [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.jboss.weld.servlet.ConversationPropagationFilter.doFilter(ConversationPropagationFilter.java:62) [weld-core-1.1.5.AS71.Final.jar:2012-02-10 15:31]
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.jpa.interceptor.WebNonTxEmCloserValve.invoke(WebNonTxEmCloserValve.java:50) [jboss-as-jpa-7.1.1.Final.jar:7.1.1.Final]
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(Unknown Source) [rt.jar:1.7.0_04]
无法找到该ID。嗯……我基本上是从RichFaces中复制了结构。那里的行按钮删除或编辑行不需要前缀：employee-form:...... 我想知道为什么。
给表单一个ID，并用“：”语法为PF组件引用添加前缀，代码将按预期运行：
<h:form id="employee-form">
<p:dataTable ...>
...
<p:column>
<h:panelGrid ...>
<p:commandButton ...
update=":employee-form:employee-remove-dialog"
...>
...
</p:commandButton>
</h:panelGrid>
</p:column>
</p:dataTable>
<p:dialog ...
id="employee-remove-dialog">
</p:dialog>
</h:form>
问:
为什么要在一个p:datatable中添加JSF ID的前缀？也许这是我的代码问题，但我觉得这个例子很简单。无论如何，这样做可能会导致应用程序中出现很长的ID。
我做错了什么吗？
PS：我使用的是JBoss AS 7.1.1.Final、Mojarra 2.1.7、PF 3.3.1