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;
@Component
public 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;
@Component
public 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脚本之家。
