1.编程式效验需要实现Validator接口，针对模型类进行校验
2.jar包
3.项目测试结构
4.StudentModel.java（模型类）
package com.wt.entity;
public class StudentModel {
private String name;
private String pwd;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPwd() {
return pwd;
}
public void setPwd(String pwd) {
this.pwd = pwd;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
}
5.StudentValidator.java（校验器）
package com.wt.entity; import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator; public class StudentValidator implements Validator{
//验证是否支持效验的StudentModel对象，匹配则执行效验
@Override
public boolean supports(Class<?> clazz) { return StudentModel.class.equals(clazz);
}
//效验数据的方法，object为效验的对象，Errors为效验的错误信息
@Override
public void validate(Object obj, Errors errors) {
//效验name和pwd属性为空时加入错误信息
ValidationUtils.rejectIfEmpty(errors, "name", null,"姓名不能为空");
ValidationUtils.rejectIfEmpty(errors, "pwd", null,"密码不能为空");
if(errors.hasErrors()){
//上面发现错误,直接返回,下面也无需效验
return;
}
//针对属性的规则进行具体效验
StudentModel stu=(StudentModel) obj;
if(stu.getName().length()<5||stu.getName().length()>10){
errors.rejectValue("name", null, "姓名长度错误，应在5~10间");
}
if(stu.getPwd().length()<8||stu.getPwd().length()>15){
errors.rejectValue("pwd", null,"密码长度错误，应在8~15之间");
}
if(stu.getAge()<=0||stu.getAge()>100){
errors.rejectValue("age", null, "年龄错误，应在1~100之间");
}
} }
6.ValidController.java(控制器)
package com.wt.entity; import org.springframework.stereotype.Controller;
import org.springframework.validation.Errors;
import org.springframework.web.bind.annotation.RequestMapping; @Controller//定义控制器
public class ValidController {
//声明效验器
StudentValidator studentValidator=new StudentValidator();
@RequestMapping(value="validstu.html")//访问路径
public String validStudent(StudentModel model,Errors errors){
studentValidator.validate(model, errors);//效验对象
if(errors.hasErrors()){//发现错误，forword到错误页面
return "Error";
}
return "result";//成功 }
}
7.springmvc-servlet.xml
<?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:p="http://www.springframework.org/schema/p"
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/context
http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd">
<!-- 注解扫描 -->
<context:component-scan base-package="com.wt.entity"/> <!-- 完成视图的对应 -->
<!-- 对转向页面的路径解析。prefix：前缀， suffix：后缀 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" >
<property name="prefix" value="/WEB-INF/jsp/example1/"/>
<property name="suffix" value=".jsp"/>
</bean> </beans>
8.web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">
<display-name>SpringMVC</display-name>
<servlet>
<servlet-name>article6</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springmvc-servlet.xml</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>article6</servlet-name>
<url-pattern>/url/*</url-pattern>
</servlet-mapping>
</web-app>
9.Errors.jsp(头部导入form标签)
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<%@taglib prefix="sf" 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>Insert title here</title>
</head>
<body>
<sf:form commandName="studentModel">
显示所有错误消息
<br>
<sf:errors path="*"/>
<br>
<br>
显示属性为age的错误信息
<br>
<sf:errors path="age"></sf:errors>
</sf:form>
</body>
</html>
10.result.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!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>Insert title here</title>
</head>
<body>
效验成功
</body>
</html>
11.测试结果
