Question

我正在尝试使用spring＆amp; amp;创建简单的注册表单冬眠。当我尝试运行程序时，我得到了bindingresult的错误。

这是我的用户pojo类

package com.kalam.model;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

import org.hibernate.validator.constraints.NotEmpty;

@Entity
@Table(name="User")
public class User {

@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long userId;

@Column
@NotEmpty(message="username can't be blank")
private String UserName = "";

@Column
@NotEmpty(message="password can't be blank")
private String Password = "";

@Column
@NotEmpty(message="Mobile can't be blank")
private int MobileNo;

@Enumerated(EnumType.ORDINAL)
private Role userRole;

public Long getUserId() {
    return userId;
}

public void setUserId(Long userId) {
    this.userId = userId;
}

public String getUserName() {
    return UserName;
}

public void setUserName(String userName) {
    UserName = userName;
}

public String getPassword() {
    return Password;
}

public void setPassword(String password) {
    Password = password;
}

public int getMobileNo() {
    return MobileNo;
}

public void setMobileNo(int mobileNo) {
    MobileNo = mobileNo;
}

public Role getUserRole() {
    return userRole;
}

public void setUserRole(Role userRole) {
    this.userRole = userRole;
}

}

这是User.jsp（注册表单）

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>   
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Registration</title>
</head>
<body>
    <div align="center">
        <form:form action="/addUser" method="post" modelAttribute="userForm">
            <table border="0">
                <tr>
                    <td colspan="2" align="center"><h2>Spring MVC Form Demo - Registration</h2></td>
                </tr>
               <tr>
                    <td>User Name:</td>
                    <td><form:input path="UserName" /></td>
                </tr>

                <tr>
                    <td>Password:</td>
                    <td><form:password path="Password" /></td>
                </tr>
                <tr>
                    <td>Mobile No:</td>
                    <td><form:input path="MobileNo" /></td>
                </tr>

                <tr>
                    <td colspan="2" align="center"><input type="submit" value="Register" /></td>
                </tr>
            </table>
        </form:form>
    </div>
</body>
</html>

最后是Controller类。

package com.kalam.controller;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import com.kalam.daoimpl.EmployeeDaoImpl;
import com.kalam.model.Employee;
import com.kalam.model.User;
import com.kalam.service.EmployeeService;
import com.kalam.serviceimpl.EmployeeServiceImpl;




@Controller

public class KalamController {

//@Autowired 
//EmployeeService employeeService;

    @RequestMapping("/kalam")
    public String showMessage(ModelMap map) {

        map.put("dollar", "50 US $");
        return "KalamWorld";
    }

    @RequestMapping("/insertData")
    public void InserData() {

        Employee emp= new Employee();
        emp.setEmpID(11);
        emp.setEmpName("On Target");
        emp.setEmpSalary(20000);
        emp.setAddress("Mumbai");


            ApplicationContext context=new ClassPathXmlApplicationContext("hibernate-cfg.xml"); 
            EmployeeDaoImpl dao= (EmployeeDaoImpl)context.getBean("employeeDaoImpl");
            dao.addEmployee(emp); 
            System.out.println("Data successfully inserted");

    //  employeeService.addEmployee(emp);  
    } 


    @RequestMapping(value ="/",method = RequestMethod.GET)
    public String login(ModelMap model) {
        User userFrom=new User();
        model.put("userFrom", userFrom);
        return "User";

    }

    @RequestMapping(value = "/addUser", method = RequestMethod.POST)
       public String addEmployee(@Valid @ModelAttribute("userFrom")User user, ModelMap model) {
          model.addAttribute("name", user.getUserName());
          model.addAttribute("Id", user.getUserId());
          model.addAttribute("Mobile", user.getMobileNo());

          return "success";
       }


    @RequestMapping(value ="/welcome",method = RequestMethod.GET)
    public String welcome(ModelMap model) {
        return "User";

    }



}

我希望在运行应用程序时将User.jsp页面显示为第一页。因此我试图调用@RequestMapping（value =“/”，method = RequestMethod.GET）处理程序。

但是当我尝试运行该程序时，我收到以下错误。

java.lang.IllegalStateException: Neither BindingResult nor plain target object for bean name 'userForm' available as request attribute
    at org.springframework.web.servlet.support.BindStatus.<init>(BindStatus.java:141)
    at org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getBindStatus(AbstractDataBoundFormElementTag.java:168)
    at org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getPropertyPath(AbstractDataBoundFormElementTag.java:188)
    at org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.getName(AbstractDataBoundFormElementTag.java:154)
    at org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.autogenerateId(AbstractDataBoundFormElementTag.java:141)
    at org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.resolveId(AbstractDataBoundFormElementTag.java:132)
    at org.springframework.web.servlet.tags.form.AbstractDataBoundFormElementTag.writeDefaultAttributes(AbstractDataBoundFormElementTag.java:116)
    at org.springframework.web.servlet.tags.form.AbstractHtmlElementTag.writeDefaultAttributes(AbstractHtmlElementTag.java:422)
    at org.springframework.web.servlet.tags.form.InputTag.writeTagContent(InputTag.java:142)
    at org.springframework.web.servlet.tags.form.AbstractFormTag.doStartTagInternal(AbstractFormTag.java:84)
    at org.springframework.web.servlet.tags.RequestContextAwareTag.doStartTag(RequestContextAwareTag.java:80)
    at org.apache.jsp.WEB_002dINF.views.User_jsp._jspx_meth_form_005finput_005f0(User_jsp.java:220)
    at org.apache.jsp.WEB_002dINF.views.User_jsp._jspx_meth_form_005fform_005f0(User_jsp.java:158)
    at org.apache.jsp.WEB_002dINF.views.User_jsp._jspService(User_jsp.java:104)
    at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
    at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:439)
    at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
    at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:743)
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:485)
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:410)
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:337)
    at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:209)
    at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:266)
    at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1225)
    at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1012)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:959)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:624)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:303)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:506)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:169)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:962)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:445)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1115)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:637)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:316)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:745)

Apr 16, 2018 9:25:25 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [dispatcher] in context with path [/KalamProject] threw exception [An exception occurred processing JSP page /WEB-INF/views/User.jsp at line 20

17:                 </tr>
18:                <tr>
19:                     <td>User Name:</td>
20:                     <td><form:input path="UserName" /></td>
21:                 </tr>
22:                
23:                 <tr>

请帮我解决错误。提前致谢

Answer 1

在User处理程序中返回视图名称之前，您需要初始化welcome对象并将其放入模型中：

@RequestMapping(value ="/welcome", method = RequestMethod.GET)
public String welcome(ModelMap model) {
    User user = new User();
    model.put("userForm", user);
    return "User";
}

或者你可以这样做以获得你想要实现的目标：

@RequestMapping(value ="/welcome", method = RequestMethod.GET)
public String welcome() {
    return "redirect:/";
}

注意：在login处理程序中

model.put("userFrom", userFrom);

应该是

model.put("userForm", userFrom);

与User.jsp
一样
...modelAttribute="userForm">

这也会显示相同的错误。

Spring中的BindingResult错误

1 个答案: