在struts 2.0中的iterator中使用复选框

时间:2011-03-07 17:48:19

标签: java struts2 iterator

在我的示例应用程序中,这非常完美

<s:iterator value="menuGroup" var="menu">
                <s:textfield value="%{#menu.name}"></s:textfield>
            </s:iterator>

但是当我使用复选框时,即`

<s:iterator value="menuGroup" var="menuLst">
                <s:checkbox value="%{menuLst.name}"></s:checkbox>
            </s:iterator>

它会出现类似

的错误
freemarker.core.InvalidReferenceException: Expression parameters.name is undefined on line 23, column 56 in template/xhtml/checkbox.ftl.
    at freemarker.core.TemplateObject.assertNonNull(TemplateObject.java:124)
    at freemarker.core.DynamicKeyName._getAsTemplateModel(DynamicKeyName.java:85)
    at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
    at freemarker.core.ExistsExpression._getAsTemplateModel(ExistsExpression.java:71)
    at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
    at freemarker.core.Expression.isTrue(Expression.java:138)
    at freemarker.core.AndExpression.isTrue(AndExpression.java:68)
    at freemarker.core.BooleanExpression._getAsTemplateModel(BooleanExpression.java:61)
    at freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
    at freemarker.core.Assignment.accept(Assignment.java:90)
    at freemarker.core.Environment.visit(Environment.java:208)
    at freemarker.core.MixedContent.accept(MixedContent.java:92)
    at freemarker.core.Environment.visit(Environment.java:208)
    at freemarker.core.Environment.process(Environment.java:188)
    at freemarker.template.Template.process(Template.java:237)
    at org.apache.struts2.components.template.FreemarkerTemplateEngine.renderTemplate(FreemarkerTemplateEngine.java:182)
    at org.apache.struts2.components.UIBean.mergeTemplate(UIBean.java:559)
    at org.apache.struts2.components.UIBean.end(UIBean.java:513)
    at org.apache.struts2.views.jsp.ComponentTagSupport.doEndTag(ComponentTagSupport.java:42)
    at org.apache.jsp.jsp.pages.system.acl_002dgroup_jsp._jspx_meth_s_005fcheckbox_005f0(acl_002dgroup_jsp.java:440)
    at org.apache.jsp.jsp.pages.system.acl_002dgroup_jsp._jspx_meth_s_005fiterator_005f0(acl_002dgroup_jsp.java:411)
    at org.apache.jsp.jsp.pages.system.acl_002dgroup_jsp._jspx_meth_s_005fform_005f0(acl_002dgroup_jsp.java:368)
    at org.apache.jsp.jsp.pages.system.acl_002dgroup_jsp._jspService(acl_002dgroup_jsp.java:317)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:322)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:249)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:638)
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:444)
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:382)
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:310)
    at org.apache.struts2.dispatcher.ServletDispatcherResult.doExecute(ServletDispatcherResult.java:154)
    at org.apache.struts2.dispatcher.StrutsResultSupport.execute(StrutsResultSupport.java:186)
    at com.opensymphony.xwork2.DefaultActionInvocation.executeResult(DefaultActionInvocation.java:361)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:265)
    at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:163)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:249)
    at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:68)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:122)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:195)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:148)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:93)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:235)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:89)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ScopedModelDrivenInterceptor.intercept(ScopedModelDrivenInterceptor.java:128)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at org.apache.struts2.interceptor.ProfilingActivationInterceptor.intercept(ProfilingActivationInterceptor.java:104)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at org.apache.struts2.interceptor.debugging.DebuggingInterceptor.intercept(DebuggingInterceptor.java:267)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ChainingInterceptor.intercept(ChainingInterceptor.java:126)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:138)
    at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:87)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:148)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.AliasInterceptor.intercept(AliasInterceptor.java:128)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:176)
    at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:236)
    at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:52)
    at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:468)
    at org.apache.struts2.dispatcher.FilterDispatcher.

1 个答案:

答案 0 :(得分:1)

写作会更直接:

<s:iterator value="menuGroup">
  <s:textfield value="name"/>
</s:iterator>

现在因为没有提供其他信息,你是否写了等价物(这是错误的btw):

<s:iterator value="menuGroup">
  <s:checkbox value="name"/>
</s:iterator>

因为您可以使用字符串命名和标记复选框,但该值必须是布尔值,因为它指的是复选框状态,不要与fieldValue属性混淆,后者等同于html复选框参数“value ”。请参阅:http://struts.apache.org/2.2.1/docs/checkbox.html

如果您发现标签是障碍,只需将复选框写为html http://www.w3schools.com/html/html_forms.asp