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I have a view 'hi.jsp' with user name and password text fields. I need to submit 'hi.jsp' to 'LoginController.java'. If there is any error in the data submitted then 'LoginController.java' must redirect the request back to 'hi.jsp' (with text fields retaning the entered data) with respective error messages. After changing data and re-submitting 'hi.jsp' I get 404 error.

So the first submission is successful however problem occurs during second submission. The source code of files is mentioned below:

hi.jsp

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
  <%@ taglib uri="http://www.springframework.org/tags/form" prefix="s" %>
  <%@ page session="false" %>
  <html>
      <body>    
        <s:form method="POST" modelAttribute="loginObj" action="login/validatelogin">
           <label for="userName">UserName</label>
           <s:input path="userName" id="userName" size="15"/><br>
           <div style="{color:red}"> <s:errors path="userName"></s:errors></div>

           <label for="password">Password</label>
           <s:input path="password" id="password" size="15" /><br>
           <s:errors path="password"></s:errors>

           <input name="submit" type="submit" value="login"/>      
    </s:form>
   </body>
</html>

LoginController.java

package rajeev.spring.spitter.mvc.controller;

import javax.validation.Valid;

import org.springframework.stereotype.Controller;
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;

@Controller
@RequestMapping("/login")
public class LoginController {

    @RequestMapping(value="/validatelogin", method=RequestMethod.POST)
    public String validateLogin(@Valid @ModelAttribute("loginObj") LoginBean loginObj, BindingResult bindingResult)
    {
        System.out.println(bindingResult.hasErrors());
        if(bindingResult.hasErrors())
        {
            return "hi";
        }
        return "home";
    }
}

spitter-servlet.xml (spring configuration)

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:jdbc="http://www.springframework.org/schema/jdbc"
    xsi:schemaLocation="http://www.springframework.org/schema/jdbc http://www.springframework.org/schema/jdbc/spring-jdbc-3.0.xsd
        http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

    <mvc:annotation-driven/>
    <context:component-scan base-package="rajeev.spring.spitter.mvc.controller"></context:component-scan>
     <bean  class="org.springframework.web.servlet.view.InternalResourceViewResolver">
    <property name="prefix" value="/WEB-INF/views/" />
    <property name="suffix" value=".jsp" />
  </bean>
</beans>

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    id="WebApp_ID" version="2.5">
    <display-name>Spring Hello World</display-name>
    <welcome-file-list>
        <welcome-file>/</welcome-file>
    </welcome-file-list>

    <servlet>
        <servlet-name>springDispatcher</servlet-name>
        <servlet-class>
            org.springframework.web.servlet.DispatcherServlet
        </servlet-class>
      <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>/WEB-INF/spitter-servlet.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springDispatcher</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>
</web-app>

During the second submission of 'hi.jsp' tomcat log also displays a warning:

WARNING: No mapping found for HTTP request with URI [/SpringMVC/login/login/validatelogin] in DispatcherServlet with name 'springDispatcher'

It seems that during second submission of 'hi.jsp' an extra '/login' is getting appended to the submission path of the form.

Kindly suggest if something is wrong with above code or do I need to modify it to make it working.

Thanks for your help.

4

2 回答 2

1

这是因为当您将处理程序方法映射到不同的 URL 时，相对表单发布 URL 发生了变化

<s:form method="POST" modelAttribute="loginObj" action="login/validatelogin">

此问题的常见解决方案是使用绝对路径，但不是硬编码，而是使用查找上下文路径

<c:set var="root" value="${pageContext.request.contextPath}"/>

然后在你的表格上

<s:form method="POST" modelAttribute="loginObj" action="${root}/login/validatelogin">

您可能考虑的其他选项是在控制器处理程序方法中使用 Post-Redirect 模式以避免切换 URL

public String validateLogin(@Valid @ModelAttribute("loginObj") LoginBean loginObj, BindingResult bindingResult) {
  ....
  return "redirect:/login";
}
于 2013-06-03T01:34:16.850 回答
0

尝试这个：

<c:url var="myAction" value="/login/validatelogin"/>
<s:form method="POST" modelAttribute="loginObj" action="${myAction}">
于 2013-06-02T23:41:47.070 回答