java - BindingResult 和 bean 名称的普通目标对象都不能用作请求属性 - Spring MVC

Question

这个问题在这里已经有了答案:





What causes "java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'command' available as request attribute"?

(6 个回答)


4年前关闭。




我收到此错误

java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'command' available as request attribute

这是堆栈跟踪

org.apache.jasper.JasperException: java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'command' available as request attribute org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:534) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:452) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333) javax.servlet.http.HttpServlet.service(HttpServlet.java:722)root cause java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'command' available as request attribute org.springframework.web.servlet.support.BindStatus.(BindStatus.java:141) org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getBindStatus(AbstractDataBoundFormElementTag.java:178) org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getPropertyPath(AbstractDataBoundFormElementTag.java:198) org.springframework.web.servlet.tags.form.LabelTag.autogenerateFor(LabelTag.java:129) org.springframework.web.servlet.tags.form.LabelTag.resolveFor(LabelTag.java:119) org.springframework.web.servlet.tags.form.LabelTag.writeTagContent(LabelTag.java:89) org.springframework.web.servlet.tags.form.AbstractFormTag.doStartTagInternal(AbstractFormTag.java:102) org.springframework.web.servlet.tags.RequestContextAwareTag.doStartTag(RequestContextAwareTag.java:79) org.apache.jsp.student_jsp._jspx_meth_form_005flabel_005f0(student_jsp.java:182) org.apache.jsp.student_jsp._jspx_meth_form_005fform_005f0(student_jsp.java:117) org.apache.jsp.student_jsp._jspService(student_jsp.java:79) org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70) javax.servlet.http.HttpServlet.service(HttpServlet.java:722) org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:419) org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:389) org.apache.jasper.servlet.JspServlet.service(JspServlet.java:333) javax.servlet.http.HttpServlet.service(HttpServlet.java:722)

这是我的 web.xml 文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4"
    xmlns="http://java.sun.com/xml/ns/j2ee" 
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee 
    http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">


    <display-name>Spring MVC Form Handling</display-name>
    <welcome-file-list>
    <welcome-file>student.jsp</welcome-file>
  </welcome-file-list>

  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>


    <servlet>
        <servlet-name>HelloWeb</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/HelloWeb-Servlet.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>   

    <servlet-mapping>
        <servlet-name>HelloWeb</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

</web-app>

这是我的 applicationContext.xml 文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:context="http://www.springframework.org/schema/context"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:mvc="http://www.springframework.org/schema/mvc"

   xsi:schemaLocation="
   http://www.springframework.org/schema/beans     
   http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
   http://www.springframework.org/schema/context 
   http://www.springframework.org/schema/context/spring-context-3.0.xsd
   http://www.springframework.org/schema/mvc
   http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">

   <context:component-scan base-package="com.Prime" />
<mvc:annotation-driven/>
   <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
      <property name="prefix" value="/WEB-INF/JSP/" />
      <property name="suffix" value=".jsp" />
   </bean>



</beans>

这是我的 student.jsp 文件

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
    pageEncoding="ISO-8859-1"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<html>
<head>
    <title>Spring MVC Form Handling</title>
</head>
<body>

<h2>Student Information</h2>
<form:form modelAttribute="SpringWeb" method="POST" action="/HelloWeb/addStudent" commandName="SpringWeb">
   <table>
    <tr>
        <td><form:label path="name">Name</form:label></td>
        <td><form:input path="name" /></td>
    </tr>
    <tr>
        <td><form:label path="age">Age</form:label></td>
        <td><form:input path="age" /></td>
    </tr>
    <tr>
        <td><form:label path="id">id</form:label></td>
        <td><form:input path="id" /></td>
    </tr>
    <tr>
        <td colspan="2">
            <input type="submit" value="Submit"/>
        </td>
    </tr>
</table>  
</form:form>
</body>
</html>

这是我的 StudentController.java 文件

package com.Prime;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.ui.ModelMap;

@Controller
public class StudentController {

   @RequestMapping(value = "/student", method = RequestMethod.GET)
   public ModelAndView student() {
      return new ModelAndView("/student.jsp", "SpringWeb", new Student());
   }

   @RequestMapping(value = "/addStudent", method = RequestMethod.POST)
   public String addStudent(@ModelAttribute("SpringWeb")Student student, 
   ModelMap model) {
      model.addAttribute("name", student.getName());
      model.addAttribute("age", student.getAge());
      model.addAttribute("id", student.getId());

      return "result";
   }
}

任何人都可以帮我解决这个错误......提前致谢

Answer 1

编辑:

我兄弟，你的异常(exception)声明“bean name 'command'”。我认为您有一些部署问题，因为您在此处发布的代码与异常不匹配。

删除 commandName来自表单标签的属性，modelAttribute属性就够了:

<form:form modelAttribute="SpringWeb" method="POST" action="/HelloWeb/addStudent" >

看完这篇 article ，看来这不是您问题的解决方案，但无论如何您不需要两次指定它们。