java - :dataTable problem - Target model Type is no a Collection or Array

Question

尽管有大量关于该主题的教程，但我确实一直在努力解决这个问题。我正在测试 JSF 2.0 中 h:dataTable 组件的功能。我有以下列表:

        <h:dataTable border="1" styleClass="data zebra" value="#{testTableWB.testList}" var="items">   
            <h:column>
              <f:facet name="header">
               <h:outputText  value="id"/>
              </f:facet>
               <h:outputText value="#{items.id}"/>
            </h:column>

            <h:column>
                <f:facet name="header">
            <h:outputText  value="name"/>
                </f:facet>
            <h:outputText value="#{items.name}"/>
            </h:column>
            <h:column>
              <f:facet name="header">
                <h:outputText  value="description"/>
              </f:facet>
               <h:outputText value="#{items.description}"/>
            </h:column>
            <h:column>
              <f:facet name="header">
              </f:facet>
                <h:selectManyCheckbox id="ids" value="#{items.id}">
                    <f:selectItem value="#{ids}" itemLabel="" />
                </h:selectManyCheckbox>
            </h:column>
            <h:column>
              <f:facet name="header">
              </f:facet>
                <h:commandLink action="testTableWB.someStupidAction" value="Edit">
                    <f:param id="itemIDEdit" value="items.id"/>
                </h:commandLink>
            </h:column>
            <h:column>
              <f:facet name="header">
              </f:facet>
                <h:commandLink action="testTableWB.someStupidAction" value="Show">
                    <f:param id="itemIDShow" value="items.id"/>
                </h:commandLink>
            </h:column>             
        </h:dataTable> 

我的托管 Bean 如下所示:

@ManagedBean(name="testTableWB")@RequestScoped公共(public)类 TestTableWBR 扩展了 VerificationWBR {

private List<TestElement> testList;

public List<TestElement> getTestList() {
    testList = new ArrayList<TestElement>();

    for (int i=0; i<5;i++){
        testList.add(new TestElement(new Long(i),"name"+i, "descrition"+i));
    }

    testList.add(new TestElement(10L,"mark", "test element"));

    return this.testList;
}

public void setTestList(List<TestElement> pTestList) {
    this.testList = pTestList;
}

public void someStupidAction(){
    String parameter =  FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get("itemIDEdit");

}

因此，当我单击其中一个命令链接 - 编辑或显示时，我期望调用该操作，并且那里有一个断点。相反，我收到错误:目标模型类型不是集合或数组以及以下堆栈跟踪:

    javax.faces.FacesException: Target model Type is no a Collection or Array
    at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValuesForModel(MenuRenderer.java:390)
    at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValue(MenuRenderer.java:127)
    at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue(MenuRenderer.java:313)
    at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1008)
    at javax.faces.component.UIInput.validate(UIInput.java:934)
    at javax.faces.component.UIInput.executeValidate(UIInput.java:1189)
    at javax.faces.component.UIInput.processValidators(UIInput.java:691)
    at javax.faces.component.UIData.iterate(UIData.java:1424)
    at javax.faces.component.UIData.processValidators(UIData.java:1015)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIForm.processValidators(UIForm.java:243)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1080)
    at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1179)
    at com.sun.faces.lifecycle.ProcessValidationsPhase.execute(ProcessValidationsPhase.java:76)
    at com.sun.faces.lifecycle.Phase.doPhase(Phase.java:101)
    at com.sun.faces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:118)
    at javax.faces.webapp.FacesServlet.service(FacesServlet.java:310)
    at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:427)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:333)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at com.bmw.verdict.web.fupload.UploadFilter.doFilter(UploadFilter.java:70)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:246)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:214)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:313)
    at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:287)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:218)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:648)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:593)
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:94)
    at com.sun.enterprise.web.PESessionLockingStandardPipeline.invoke(PESessionLockingStandardPipeline.java:98)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:222)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:648)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:593)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:587)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1093)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:166)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:648)
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:593)
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:587)
    at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:1093)
    at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:291)
    at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.invokeAdapter(DefaultProcessorTask.java:666)
    at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.doProcess(DefaultProcessorTask.java:597)
    at com.sun.enterprise.web.connector.grizzly.DefaultProcessorTask.process(DefaultProcessorTask.java:872)
    at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.executeProcessorTask(DefaultReadTask.java:341)
    at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:263)
    at com.sun.enterprise.web.connector.grizzly.DefaultReadTask.doTask(DefaultReadTask.java:214)
    at com.sun.enterprise.web.portunif.PortUnificationPipeline$PUTask.doTask(PortUnificationPipeline.java:382)
    at com.sun.enterprise.web.connector.grizzly.TaskBase.run(TaskBase.java:264)
    at com.sun.enterprise.web.connector.grizzly.ssl.SSLWorkerThread.run(SSLWorkerThread.java:106)

根据文档，dataTable 组件应使用 List 数据类型。我根本没有接触到托管 bean，所以我猜想在此之前的生命周期中出现了问题。那么我哪里出错了？感谢您提前提供的帮助。

问候，大家

Answer 1

好的，解决了。使用 secletBooleanCheckBox 代替。