com.sun.faces.renderkit.html_basic.MenuRenderer createCollection:无法为类型java.util.Arrays $ ArrayList创建新的Collection实例

Question

我正在尝试使用带枚举的JSF/SelectManyCheckBox标记:

这是我的xhtml代码:

            <h:form id="searchForm">
                <h:panelGrid columns="2">
                    <h:outputText value="Searched queues" />
                    <h:panelGroup>
                        <h:selectManyCheckbox layout="pageDirection" value="#{jmsErrorController.errorSearchCriteria.searchedQueues}" converter="queueConverter">
                            <f:selectItems value="#{jmsErrorController.completeQueueList}" />
                        </h:selectManyCheckbox>
                    </h:panelGroup>
                </h:panelGrid>
                <h:commandButton action="#{jmsErrorController.search}"
                    value="Search !" />
            </h:form>

我添加了另一篇文章中所述的转换器.

它似乎工作正常,但我在控制台上看到这个堆栈跟踪:

28-Jun-2013 09:07:46 com.sun.faces.renderkit.html_basic.MenuRenderer createCollection
SEVERE: Unable to create new Collection instance for type java.util.Arrays$ArrayList
java.lang.InstantiationException: java.util.Arrays$ArrayList
at java.lang.Class.newInstance0(Class.java:340)
at java.lang.Class.newInstance(Class.java:308)
at com.sun.faces.renderkit.html_basic.MenuRenderer.createCollection(MenuRenderer.java:907)
at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValuesForModel(MenuRenderer.java:367)
at com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValue(MenuRenderer.java:129)
at com.sun.faces.renderkit.html_basic.MenuRenderer.getConvertedValue(MenuRenderer.java:315)
at javax.faces.component.UIInput.getConvertedValue(UIInput.java:1030)
at javax.faces.component.UIInput.validate(UIInput.java:960)
at javax.faces.component.UIInput.executeValidate(UIInput.java:1233)
at javax.faces.component.UIInput.processValidators(UIInput.java:698)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1214)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1214)
at javax.faces.component.UIForm.processValidators(UIForm.java:253)
at javax.faces.component.UIComponentBase.processValidators(UIComponentBase.java:1214)
at javax.faces.component.UIViewRoot.processValidators(UIViewRoot.java:1172)
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:593)
at weblogic.servlet.internal.StubSecurityHelper$ServletServiceAction.run(StubSecurityHelper.java:227)
at weblogic.servlet.internal.StubSecurityHelper.invokeServlet(StubSecurityHelper.java:125)
at weblogic.servlet.internal.ServletStubImpl.execute(ServletStubImpl.java:300)
at weblogic.servlet.internal.TailFilter.doFilter(TailFilter.java:26)
at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
at weblogic.servlet.internal.RequestEventsFilter.doFilter(RequestEventsFilter.java:27)
at weblogic.servlet.internal.FilterChainImpl.doFilter(FilterChainImpl.java:56)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.doIt(WebAppServletContext.java:3684)
at weblogic.servlet.internal.WebAppServletContext$ServletInvocationAction.run(WebAppServletContext.java:3650)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:321)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:121)
at weblogic.servlet.internal.WebAppServletContext.securedExecute(WebAppServletContext.java:2268)
at weblogic.servlet.internal.WebAppServletContext.execute(WebAppServletContext.java:2174)
at weblogic.servlet.internal.ServletRequestImpl.run(ServletRequestImpl.java:1446)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:173)

在这个堆栈跟踪之后,应用程序似乎工作正常,但我想知道为什么会有这样的堆栈跟踪..

有人能帮我吗？

谢谢.

斯特凡.

Answer 1

当使用方法而不是使用方法创建提供的UISelectMany组件时,会发生这种情况.valueArrays#asList()new ArrayList()

如果模型value已经预先填充,JSF将尝试使用完全相同的类型将提交的值放入并设置新的模型值.但是,java.util.Arrays$ArrayList返回的类型Arrays#asList()是java.util.Arrays类的内部类型,而不是单独可实例化的类型new Arrays$ArrayList().因此这个例外.

要解决此问题,请确保使用创建值new ArrayList().

或者,collectionType按照此紧密相关的答案中的指示显式指定集合类型:com.sun.faces.renderkit.html_basic.MenuRenderer.convertSelectManyValuesForModel中的org.hibernate.LazyInitializationException.

<h:selectManyCheckbox ... collectionType="java.util.ArrayList">