JSF状态保存和自定义组件以及动态添加的子代 [英] JSF State saving and custom components with dynamically added children

问题描述

我正在开发一个JSF定制组件.该组件的目的是封装另一个组件(即PrimeFaces表)并为其添加自定义行为.例如，它支持的功能之一是根据基础数据或某些属性动态创建PrimeFaces列.此外，它支持在XHTML中声明其他PrimeFaces列，这些列也应添加到封装的PrimeFaces表中.

请考虑以下示例:

<my:table id="table" fields="title,label,value,additional">
    <primefaces:column id="additional">
        some content
    </primefaces:column>
</my:table>

我的自定义组件在渲染过程中根据fields属性动态创建PrimeFaces列.然后将其所有column子级移动到PrimeFaces表中，因此在渲染组件树后如下所示:

my:table id="table"
|---primefaces:table id="table_table"
    |---primefaces:column id="title"
    |---primefaces:column id="label"
    |---primefaces:column id="value"
    |---primefaces:column id="additional"

在第一次渲染期间，这可以正常工作.但是，当我随后对组件执行AJAX更新时，出现以下异常:

javax.faces.FacesException: Cannot remove the same component twice: table:additional
    at com.sun.faces.context.StateContext$DynamicAddRemoveListener.handleAddRemoveWithAutoPrune(StateContext.java:761)
    at com.sun.faces.context.StateContext$DynamicAddRemoveListener.handleRemove(StateContext.java:629)
    at com.sun.faces.context.StateContext$AddRemoveListener.processEvent(StateContext.java:342)
    at com.sun.faces.context.StateContext$DynamicAddRemoveListener.processEvent(StateContext.java:565)
    at javax.faces.event.SystemEvent.processListener(SystemEvent.java:108)
    at javax.faces.event.ComponentSystemEvent.processListener(ComponentSystemEvent.java:118)
    at com.sun.faces.application.ApplicationImpl.processListenersAccountingForAdds(ApplicationImpl.java:2218)
    at com.sun.faces.application.ApplicationImpl.invokeViewListenersFor(ApplicationImpl.java:2036)
    at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:290)
    at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:245)
    at javax.faces.application.ApplicationWrapper.publishEvent(ApplicationWrapper.java:726)
    at javax.faces.component.UIComponentBase.disconnectFromView(UIComponentBase.java:2275)
    at javax.faces.component.UIComponentBase.doPreRemoveProcessing(UIComponentBase.java:1939)
    at javax.faces.component.UIComponentBase.setParent(UIComponentBase.java:437)
    at javax.faces.component.UIComponentBase$ChildrenList.remove(UIComponentBase.java:2757)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.adjustIndexOfDynamicChildren(ComponentTagHandlerDelegateImpl.java:283)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:223)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.ui.DefineHandler.applyDefinition(DefineHandler.java:106)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:206)
    at com.sun.faces.facelets.impl.DefaultFaceletContext$TemplateManager.apply(DefaultFaceletContext.java:395)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeDefinition(DefaultFaceletContext.java:366)
    at com.sun.faces.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:111)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:194)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:312)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:371)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:350)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:199)
    at com.sun.faces.facelets.tag.ui.IncludeHandler.apply(IncludeHandler.java:124)
    at com.sun.faces.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:116)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.ui.DefineHandler.applyDefinition(DefineHandler.java:106)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:206)
    at com.sun.faces.facelets.impl.DefaultFaceletContext$TemplateManager.apply(DefaultFaceletContext.java:395)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeDefinition(DefaultFaceletContext.java:366)
    at com.sun.faces.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:111)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.jsf.core.ViewHandler.apply(ViewHandler.java:225)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:312)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:371)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:350)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:199)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:174)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:312)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:371)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:350)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:199)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:174)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:161)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.buildView(FaceletViewHandlingStrategy.java:1006)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:99)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
    at de.gebit.trend.servlet.security.AuthorizationFilter.doFilter(AuthorizationFilter.java:269)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)

因此，只有从我的表移动到PrimeFaces表的column才创建此错误.其他列不会重新创建，因为在渲染过程中，我使用存储在StateHelper中的实例变量来指示已经创建了列.

我以某种方式理解了此异常的来源，它与JSF保存整个组件树有关，并且当JSF还原视图时，保存的状态与XHTML不一致.我不知道的是，如何解决这个问题.

有人可以向我解释一下这种状态保存机制是如何工作的，特别是与动态添加的子代一起使用时，以及如何避免这种异常?

更新(10.02.2017)

我创建了一个小的示例项目，没有以前使用的其他框架.可以在我的 GitHub个人资料中找到.以前使用的一个主要框架是在StateContext中安装了AddRemoveListeners来重播动态动作.为了避免这种情况影响我的问题并创建可重现的环境，我删除了它们.

我现在看到的行为略有不同(不再有例外)，并且取决于是否启用/禁用了部分状态保存以及我用来移动primefaces:column的方法:

在所有情况下，表的第一个呈现都可以正常工作.然后，我通过提交分页请求来执行回发请求.在某些情况下，这种行为是错误的.

已启用部分状态保存

启用部分状态保存后，分页不起作用.我没有例外，但是有很多类似的警告:

Feb 10, 2017 4:33:11 PM com.sun.faces.application.view.FaceletPartialStateManagementStrategy saveDynamicActions
WARNUNG: Unable to save dynamic action with clientId 'form:table:table_table:additional' because the UIComponent cannot be found

对于在primefaces:table中动态创建或移动到的任何组件，或者是其中一个组件的子组件，都会出现此警告.

已禁用部分状态保存

在禁用了部分状态保存的情况下，分页确实可以工作，但是根据移动一个自定义primefaces:column的时间而显示不同的行为.

在渲染响应阶段移动列"

在渲染响应阶段移动primefaces:column时，例如在encodeXxx中，一切正常.所有列的顺序正确，值正确，分页效果很好.

使用"PostAddToViewEvent"移动列"

使用此方法时，根据 @BalusC 的建议，移动的primefaces:column在分页时消失.在处理此事件时，多次调用了PostAddToViewEvent，并移动了column，但是在渲染时，它消失了，只有三个以前创建的column仍然存在.

在这一点上，我感到非常困惑.这是Mojarra或Primefaces中的错误，还是我做错了什么?使用JSF甚至可以进行这种行为吗?

解决方案

简单的答案是:正在使用其他框架错误.该框架将覆盖JSF的状态保存机制，并用自定义机制替换它.但是，该实现存在错误，没有照顾到负责正确保存动态组件动作的DynamicAddRemoveListener.他们修复了该错误，现在可以正常工作了.

但是，我想指出一些修复我的组件所必需的东西:

First ， @BalusC 向我指出了在自定义JSF组件中移动子组件的正确方法:应该使用PostAddToView事件监听器完成.

@ListenerFor(systemEventClass=PostAddToViewEvent.class)
public class YourComponent extends SomeUIComponent {

     @Override
     public void processEvent(ComponentSystemEvent event) {
          if (event instanceof PostAddToViewEvent) {
              targetParent.getChildren().add(componentToMove);
          }
     }
}

这种方法的缺点是，此时不会设置组件属性.因此，如果需要这些组件，则只能在渲染响应阶段创建/移动组件.

第二，不应将自定义JSF组件的子组件保存在StateHelper中.应该在每次请求时都重新创建它们，以便JSF在重播动态操作时找到这些组件.

第三，应在创建组件本身时始终设置动态创建的子组件的ID(如果已设置).我的自定义组件仅在渲染响应阶段设置其子组件的ID，因此，当JSF尝试重播动态动作时，它找不到相应的组件.这是启用部分状态保存部分中上述问题的解决方案.

因此，通过所有这些调整以及对其他框架的修复，现在我的组件终于可以按需工作了.

I am developing a JSF custom component. This component has the purpose of encapsulating another component (namely a PrimeFaces table) and adding customized behaviour to it. For example, one of the features that it supports is creating PrimeFaces columns dynamically from the underlying data or from certain attributes. Furthermore, it supports declaring additional PrimeFaces columns in XHTML, which should be added to the encapsulated PrimeFaces table as well.

Consider this example:

<my:table id="table" fields="title,label,value,additional">
    <primefaces:column id="additional">
        some content
    </primefaces:column>
</my:table>

My custom component dynamically creates the PrimeFaces columns from the fields attribute during rendering. It then moves all its column children to the PrimeFaces table, so after rendering the component tree looks like follows:

my:table id="table"
|---primefaces:table id="table_table"
    |---primefaces:column id="title"
    |---primefaces:column id="label"
    |---primefaces:column id="value"
    |---primefaces:column id="additional"

During first rendering, this works fine. However, when I then perform an AJAX update of my component, I get the following exception:

javax.faces.FacesException: Cannot remove the same component twice: table:additional
    at com.sun.faces.context.StateContext$DynamicAddRemoveListener.handleAddRemoveWithAutoPrune(StateContext.java:761)
    at com.sun.faces.context.StateContext$DynamicAddRemoveListener.handleRemove(StateContext.java:629)
    at com.sun.faces.context.StateContext$AddRemoveListener.processEvent(StateContext.java:342)
    at com.sun.faces.context.StateContext$DynamicAddRemoveListener.processEvent(StateContext.java:565)
    at javax.faces.event.SystemEvent.processListener(SystemEvent.java:108)
    at javax.faces.event.ComponentSystemEvent.processListener(ComponentSystemEvent.java:118)
    at com.sun.faces.application.ApplicationImpl.processListenersAccountingForAdds(ApplicationImpl.java:2218)
    at com.sun.faces.application.ApplicationImpl.invokeViewListenersFor(ApplicationImpl.java:2036)
    at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:290)
    at com.sun.faces.application.ApplicationImpl.publishEvent(ApplicationImpl.java:245)
    at javax.faces.application.ApplicationWrapper.publishEvent(ApplicationWrapper.java:726)
    at javax.faces.component.UIComponentBase.disconnectFromView(UIComponentBase.java:2275)
    at javax.faces.component.UIComponentBase.doPreRemoveProcessing(UIComponentBase.java:1939)
    at javax.faces.component.UIComponentBase.setParent(UIComponentBase.java:437)
    at javax.faces.component.UIComponentBase$ChildrenList.remove(UIComponentBase.java:2757)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.adjustIndexOfDynamicChildren(ComponentTagHandlerDelegateImpl.java:283)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:223)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.ui.DefineHandler.applyDefinition(DefineHandler.java:106)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:206)
    at com.sun.faces.facelets.impl.DefaultFaceletContext$TemplateManager.apply(DefaultFaceletContext.java:395)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeDefinition(DefaultFaceletContext.java:366)
    at com.sun.faces.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:111)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:194)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:312)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:371)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:350)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:199)
    at com.sun.faces.facelets.tag.ui.IncludeHandler.apply(IncludeHandler.java:124)
    at com.sun.faces.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:116)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.ui.DefineHandler.applyDefinition(DefineHandler.java:106)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:206)
    at com.sun.faces.facelets.impl.DefaultFaceletContext$TemplateManager.apply(DefaultFaceletContext.java:395)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeDefinition(DefaultFaceletContext.java:366)
    at com.sun.faces.facelets.tag.ui.InsertHandler.apply(InsertHandler.java:111)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.tag.jsf.core.ViewHandler.apply(ViewHandler.java:225)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.applyNextHandler(DelegatingMetaTagHandler.java:137)
    at com.sun.faces.facelets.tag.jsf.ComponentTagHandlerDelegateImpl.apply(ComponentTagHandlerDelegateImpl.java:202)
    at javax.faces.view.facelets.DelegatingMetaTagHandler.apply(DelegatingMetaTagHandler.java:120)
    at javax.faces.view.facelets.CompositeFaceletHandler.apply(CompositeFaceletHandler.java:95)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:312)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:371)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:350)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:199)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:174)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:312)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:371)
    at com.sun.faces.facelets.impl.DefaultFacelet.include(DefaultFacelet.java:350)
    at com.sun.faces.facelets.impl.DefaultFaceletContext.includeFacelet(DefaultFaceletContext.java:199)
    at com.sun.faces.facelets.tag.ui.CompositionHandler.apply(CompositionHandler.java:174)
    at com.sun.faces.facelets.compiler.NamespaceHandler.apply(NamespaceHandler.java:93)
    at com.sun.faces.facelets.compiler.EncodingHandler.apply(EncodingHandler.java:87)
    at com.sun.faces.facelets.impl.DefaultFacelet.apply(DefaultFacelet.java:161)
    at com.sun.faces.application.view.FaceletViewHandlingStrategy.buildView(FaceletViewHandlingStrategy.java:1006)
    at com.sun.faces.lifecycle.RenderResponsePhase.execute(RenderResponsePhase.java:99)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.render(LifecycleImpl.java:219)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:647)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
    at de.gebit.trend.servlet.security.AuthorizationFilter.doFilter(AuthorizationFilter.java:269)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:108)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:620)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Unknown Source)

So, only the column that was moved from my table to the PrimeFaces table is creating this error. The other columns do not get recreated, because during rendering, I use an instance variable stored in the StateHelper to indicate that columns are already created.

I somehow understand where this exception is coming from and that it has something to do with JSF saving the complete component tree, and when JSF restores the view, the saved state is inconsistent with the XHTML. What I don't know is, how to solve this problem.

Could someone please explain to me how this state saving mechanism exactly works, especially in conjunction with dynamically added children and how to avoid this exception?

UPDATE (10.02.2017)

I've created a small sample project without additional frameworks that were in use before. It can be found on my GitHub profile. One main framework that was in use before was fiddeling with the AddRemoveListeners installed in the StateContext for replaying dynamic actions. To avoid this having an impact on my issue and to create a reproducible environment, I removed them.

The behavior I witness now is slightly different (there are no exceptions anymore) and depends on whether partial state saving is enabled/disabled and the method I use to move the primefaces:column:

The first rendering of the table in all cases works fine. I then perform a postback request by submitting a paging request. The behavior then is erronous in some cases.

Partial state saving enabled

With partial state saving enabled, paging does not work. I do not get an exception, but a lot of warnings similar to this:

Feb 10, 2017 4:33:11 PM com.sun.faces.application.view.FaceletPartialStateManagementStrategy saveDynamicActions
WARNUNG: Unable to save dynamic action with clientId 'form:table:table_table:additional' because the UIComponent cannot be found

This warning appears for every component that was moved dynamically created in or moved to the primefaces:table or was a child component of one of those.

Partial state saving disabled

With partial state saving disabled, paging does work but shows different behavior depending on when the one custom primefaces:column is moved.

Moving of `column` during render response phase

When the primefaces:column is moved during render response phase, e.g. in encodeXxx, everything works fine. All the columns are in the correct order and with correct values and paging works perfectly fine.

Moving of `column` using a `PostAddToViewEvent`

When using this approach, as per @BalusC suggestion, the moved primefaces:column disappears on paging. The PostAddToViewEvent is called several times and the column is moved while handling this event, however on rendering, it has disappeared and only the three previously created columns are still there.

At this point, I am more than confused. Is this a bug in Mojarra or in Primefaces or am I doing something wrong? Is this kind of behavior even possible with JSF?

解决方案

The simple answer is: it is the other frameworks fault that is in use. This framework overwrites the state saving mechanism of JSF and replaces it with a custom mechanism. The implementation, however, was faulty and did not take care of the DynamicAddRemoveListeners responsible for saving the actions of dynamic componants correctly. They fixed the bug, now it works fine.

However, there were several things that were necessary to fix my component that I want to point out:

First, @BalusC pointed me to the correct way of moving child components in a custom JSF component: it should be done using a PostAddToView event listener.

@ListenerFor(systemEventClass=PostAddToViewEvent.class)
public class YourComponent extends SomeUIComponent {

     @Override
     public void processEvent(ComponentSystemEvent event) {
          if (event instanceof PostAddToViewEvent) {
              targetParent.getChildren().add(componentToMove);
          }
     }
}

This approach has the drawback, however, that the components attributes won't be set at this point. So if you need those, components can only be created/moved during render response phase.

Second, child components of a custom JSF component should not be saved in the StateHelper. They should be recreated on every request so that JSF finds these components when replaying the dynamic actions.

Third, the ID of dynamically created child components (if set) should always be set when the component is created itself. My custom component set the ID of its children components only during render response phase, so when JSF tried to replay the dynamic actions, it could not find the respective components. This was the solution to the problem mentioned above in the section Partial state saving enabled.

So with all these adaptions and the fix for the other framework, now finally my component works as desired.

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