Spring MVC的Validation校验

叁歲伎倆 2021-07-24 20:31 490阅读 0赞

**一 领域模型**

package org.fkit.domain;
    import java.io.Serializable;
    
    // 域对象，实现序列化接口
    public class User implements Serializable{
         
         private static final long serialVersionUID = 1L;
         
         private String loginname;
         private String password;
         public User() {
               super();
               // TODO Auto-generated constructor stub
         }
         public String getLoginname() {
               return loginname;
         }
         public void setLoginname(String loginname) {
               this.loginname = loginname;
         }
         public String getPassword() {
               return password;
         }
         public void setPassword(String password) {
               this.password = password;
         }
         @Override
         public String toString() {
               return "User [loginname=" + loginname + ", password="  + password + "]";
         }
    }

**二 校验器**

package org.fkit.validator;
    
    import org.fkit.domain.User;
    import org.springframework.stereotype.Repository;
    import org.springframework.validation.Errors;
    import org.springframework.validation.ValidationUtils;
    import org.springframework.validation.Validator;
    
    
    // 实现Spring的Validator接口
    @Repository("userValidator")
    public class UserValidator implements Validator {
    
        // 该校验器能够对clazz类型的对象进行校验。
        @Override
        public boolean supports(Class<?> clazz) {
            // User指定的 Class 参数所表示的类或接口是否相同，或是否是其超类或超接口。
            return User.class.isAssignableFrom(clazz);
        }
    
        // 对目标类target进行校验，并将校验错误记录在errors当中
        @Override
        public void validate(Object target, Errors errors) {
            /**
            使用ValidationUtils中的一个静态方法rejectIfEmpty()来对loginname属性进行校验，
            假若'loginname'属性是 null 或者空字符串的话，就拒绝验证通过 。
            */
            ValidationUtils.rejectIfEmpty(errors, "loginname", null, "登录名不能为空");  
            ValidationUtils.rejectIfEmpty(errors, "password", null, "密码不能为空");  
            User user = (User)target;
            if(user.getLoginname().length() > 10){
                // 使用Errors的rejectValue方法验证
                errors.rejectValue("loginname", null, "用户名不能超过10个字符");
            }
            if(user.getPassword() != null
                    && !user.getPassword().equals("")
                    && user.getPassword().length() < 6){
                errors.rejectValue("password", null, "密码不能小于6位");
            }
        }
    
    }

**三 控制器**

package org.fkit.controller;
    
    import org.fkit.domain.User;
    import org.fkit.validator.UserValidator;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Qualifier;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.validation.Errors;
    import org.springframework.web.bind.annotation.GetMapping;
    import org.springframework.web.bind.annotation.ModelAttribute;
    import org.springframework.web.bind.annotation.PostMapping;
    
    @Controller
    public class UserController{
         
        // 注入UserValidator对象
        @Autowired
        @Qualifier("userValidator")
        private UserValidator userValidator;
        
        @GetMapping(value="/loginForm")
         public String loginForm(Model model){
            User user = new User();
            model.addAttribute("user",user);
            // 跳转到登录页面
            return "loginForm";
        }
         
         @PostMapping(value="/login")
         public String login(
                 @ModelAttribute User user,
                 Model model,
                 Errors errors) {
             System.out.println(user);
             model.addAttribute("user", user);
             // 调用userValidator的验证方法
             userValidator.validate(user, errors);
             // 如果验证不通过跳转到loginForm视图
             if(errors.hasErrors()){
                 return "loginForm";
             }
             return "success";
         }
    
    }

**四 配置文件**

<?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:p="http://www.springframework.org/schema/p"
        xmlns:c="http://www.springframework.org/schema/c"
        xmlns:mvc="http://www.springframework.org/schema/mvc"
         xmlns:context="http://www.springframework.org/schema/context"
        xsi:schemaLocation="
            http://www.springframework.org/schema/beans
             http://www.springframework.org/schema/beans/spring-beans.xsd
            http://www.springframework.org/schema/mvc
            http://www.springframework.org/schema/mvc/spring-mvc.xsd     
            http://www.springframework.org/schema/context
             http://www.springframework.org/schema/context/spring-context.xsd">
            
        
        <context:component-scan base-package="org.fkit"/>
        
        <mvc:annotation-driven/>
         
        <mvc:default-servlet-handler/>
            
        
         <bean id="viewResolver"
               class="org.springframework.web.servlet.view.InternalResourceViewResolver"
              p:prefix="/WEB-INF/content/" p:suffix=".jsp"/>
        
    </beans>

**五 视图**

1 loginForm.jsp

<%@ 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>测试Validator接口验证</title>
    </head>
    <body>
    <h3>登录页面</h3>
    
    <form:form modelAttribute="user" method="post" action="login" >
         <table>
               <tr>
                    <td>登录名:</td>
                    <td><form:input path="loginname"/></td>
                    
                    <td><form:errors path="loginname" cssStyle=  "color:red"/></td>
              </tr>
               <tr>
                    <td>密码:</td>
                    <td><form:input path="password"/></td>
                    
                    <td><form:errors path="password" cssStyle=  "color:red"/></td>
               </tr>
               <tr>
                    <td><input type="submit" value="提交"/></td>
               </tr>
         </table>
    </form:form>
    </body>
    </html>

2 success.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt"%>
    <!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>测试ConversionService</title>
    </head>
    <body>
    登录名：${requestScope.user.loginname }
    登录名：${requestScope.user.password }
    </body>
    </html>

**六 测试**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2NoZW5ncWl1bWluZw_size_16_color_FFFFFF_t_70]: /images/20210724/63fac4da6350483aaa10e15b5c374af4.png