Spring MVC Validator @InitBinder and WebDataBinder;Validator是一个用来我们自定义验证的sping接口,WebDataBinder 绑定你的自定义参数,你直接在你的控制器类中通过@InitBinder 注解的方式配置 Web 数据绑定.registerCustomEditor()是一个属性编辑器,比如自定义的日期编辑它绑定web请求参数到JavaBean的属性;

下面一个例子,我们创建一个JavaBean(username, password, email and date of birth of a user),我们创建两个自定义的验证类.第一个,我们验证用户名和密码.第二个,验证邮箱,

在Eclipse中Demo的结构

Validator 是一个有两个方法的接口;

boolean supports(Class<?> clazz) : 检验参数是否验证成功的实例类;

void validate(Object target, Errors errors) : 如果 supports() 方法返回真, target object 合法. Errors.rejectValue() 方法用一个字段名注册错误信息;

UserValidator.java

package com.concretepage.validators;import org.springframework.stereotype.Component;import org.springframework.validation.Errors;import org.springframework.validation.ValidationUtils;import org.springframework.validation.Validator;import com.concretepage.User;@Componentpublic class UserValidator implements Validator { @Override public boolean supports(Class<?> clazz) { return User.class.isAssignableFrom(clazz); } @Override public void validate(Object target, Errors errors) { User user = (User)target; ValidationUtils.rejectIfEmptyOrWhitespace(errors, "name", "","Username is empty"); ValidationUtils.rejectIfEmptyOrWhitespace(errors, "password", "", "Password is empty"); if (user.getName().length()<5) { errors.rejectValue("name","", "Username length is less than 5"); } }}

EmailValidator.java

package com.concretepage.validators;import org.springframework.stereotype.Component;import org.springframework.validation.Errors;import org.springframework.validation.ValidationUtils;import org.springframework.validation.Validator;import com.concretepage.User;@Componentpublic class EmailValidator implements Validator { @Override public boolean supports(Class<?> clazz) { return User.class.isAssignableFrom(clazz); } @Override public void validate(Object target, Errors errors) { User user = (User)target; ValidationUtils.rejectIfEmptyOrWhitespace(errors, "email", "","Email is empty"); if (!user.getEmail().contains("@")) { errors.rejectValue("email","", "Email is not valid."); } }}

User.java

package com.concretepage;import java.util.Date;public class User { private String name; private String password; private String email; private Date dob; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } public Date getDob() { return dob; } public void setDob(Date dob) { this.dob = dob; }}

MyWorldController

package com.concretepage;import java.text.SimpleDateFormat;import java.util.Date;import javax.validation.Valid;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.beans.propertyeditors.CustomDateEditor;import org.springframework.stereotype.Controller;import org.springframework.ui.ModelMap;import org.springframework.validation.BindingResult;import org.springframework.web.bind.WebDataBinder;import org.springframework.web.bind.annotation.InitBinder;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 com.concretepage.validators.EmailValidator;import com.concretepage.validators.UserValidator;@Controller@RequestMapping("/myworld")public class MyWorldController { @Autowired private UserValidator userValidator; @Autowired private EmailValidator emailValidator; @RequestMapping(value="signup", method = RequestMethod.GET) public ModelAndView user(){ return new ModelAndView("user","user",new User()); } @InitBinder public void dataBinding(WebDataBinder binder) { binder.addValidators(userValidator, emailValidator); SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy"); dateFormat.setLenient(false); binder.registerCustomEditor(Date.class, "dob", new CustomDateEditor(dateFormat, true)); } @RequestMapping(value="save", method = RequestMethod.POST) public String createUser(@ModelAttribute("user") @Valid User user,BindingResult result, ModelMap model) { if(result.hasErrors()) { return "user"; } System.out.println("Name:"+ user.getName()); System.out.println("Email:"+ user.getEmail()); System.out.println("Date of Birth:"+ user.getDob()); model.addAttribute("msg", "Welcome to My World!"); return "success"; } }

Form页面表单

<form:form action="save" method="post" commandName="user"> <tr> <td>User Name:</td> <td><form:input path="name"/> </td> <td> <form:errors path="name" cssStyle="color: red;"/></td> </tr> <tr> <td> Password :</td> <td><form:input path="password"/> </td> <td> <form:errors path="password" cssStyle="color: red;"/> </td> </tr> <tr> <td> Email :</td> <td><form:input path="email"/> </td> <td> <form:errors path="email" cssStyle="color: red;"/> </td> </tr> <tr> <td> Date of Birth :</td> <td><form:input path="dob"/> </td> <td> <form:errors path="dob" cssStyle="color: red;"/> </td> </tr> <tr> <td colspan=3> <input type="submit"> </td> </form:form>

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。