使用JSR-303规范实现Spring MVC数据验证
二、加载依赖
JSR-303只是一个规范,而Spring也没有对这一规范进行实现,那么当我们在Spring MVC中需要使用到JSR-303的时候就需要我们提供一个对JSR-303规范的实现,Hibernate Validator是实现了这一规范,所以在项目中加入Hibernate Validator的依赖。 JSR-303的校验是基于注解的,它内部已经定义好了一系列的限制注解,我们只需要把这些注解标记在需要验证的实体类的属性上或是其对应的get方法上,常见的注解标记和含义请参考其他资料。
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-validator</artifactId>
<version>5.2.2.Final</version>
</dependency>
三、在实体类中注解验证信息
package cn.com.bochy.entity;
import java.io.Serializable;
import javax.validation.constraints.Pattern;
import org.hibernate.validator.constraints.Email;
import org.hibernate.validator.constraints.NotEmpty;
import org.hibernate.validator.constraints.Range;
public class User implements Serializable{
private static final long serialVersionUID = 1L;
@Range(min=0,max=120,message="年龄的范围为0-120")
private int age;
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public User() {
// TODO Auto-generated constructor stub
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@NotEmpty(message="名字不能为空!")
private String name;
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
@Email(message="电子信箱的格式不正确!")
private String email;
@Pattern(regexp="^/[a-zA-Z0-9_]/$",message="密码只能由a-z,A-Z,0-9和_构成")
private String password;
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
}
四、在控制器中编写验证代码
package cn.com.bochy.springmvc.controller;
import javax.validation.Valid;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.RequestMapping;
import cn.com.bochy.entity.User;
@Controller //控制器
public class DataValidController {
@RequestMapping("/login")
public String helloSpring(Model m){
m.addAttribute("user", new User());
return "add";
}
@RequestMapping("/addUser")
public String addUser(@Valid User user,BindingResult result){
if(result.hasErrors()){
return "add";
}
return "success";
}
}
注意1:BindingResult result只能写在被验证对象的后面,否则没有通过验证会报400
注意2:在使用commandName="user"之前,一定要创建一个或者绑定一个user对象,否则会报错:Spring
MVC中Neither BindingResult nor plain target object for bean name 'user' available as request,参考文章:http://blog.****.net/fullstackchenzf/article/details/72636307
@RequestMapping("/login")
public String helloSpring(Model m){
m.addAttribute("user", new User());
return "login";
}
五、配置
在spring mvc的配置文件中,加入<mvc:annotation-driven/>
六、页面
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML>
<html>
<head>
<base href="<%=basePath%>">
<title>Spring MVC数据验证</title>
<style type="text/css">
.red{
color: red;
}
</style>
</head>
<body>
<form:form action="addUser.do" method="post" commandName="user">
<table>
<tr>
<td>年龄</td>
<td><form:input path="age" name="age"/></td>
<td><form:errors path="age" cssClass="red"/></td>
</tr>
<tr>
<td>名字</td>
<td><form:input path="name" name="name"/></td>
<td><form:errors path="name" cssClass="red"/></td>
</tr>
<tr>
<td>email</td>
<td><form:input path="email" name="email"/></td>
<td><form:errors path="email" cssClass="red"/></td>
</tr>
<tr>
<td>password</td>
<td><form:input path="password" name="password"/></td>
<td><form:errors path="password" cssClass="red"/></td>
</tr>
<tr>
<td></td>
<td><input type="submit" value="提交"/></td>
<td></td>
</tr>
</table>
</form:form>
</body>
</html>