java框架之springmvc06（数据验证）

清疚 2022-09-23 00:28 31阅读 0赞

在springmvc环境搭好后还需导入数据验证jar包：[http://pan.baidu.com/s/1pKKC4kz][http_pan.baidu.com_s_1pKKC4kz]

![Center][]

person.java(注释验证)

package com.dx.pojo;  
  
import javax.validation.constraints.Size;  
import org.hibernate.validator.constraints.NotEmpty;  
  
public class Person \{  
  
@NotEmpty(message="用户名不能为空")  
private String username;  
  
@Size(min=6,message="密码长度不能小于6位")  
private String password;  
  
public String getUsername() \{  
return username;  
\}  
public void setUsername(String username) \{  
this.username = username;  
\}  
public String getPassword() \{  
return password;  
\}  
public void setPassword(String password) \{  
this.password = password;  
\}  
  
@Override  
public String toString() \{  
return "Person \[username=" + username + ", password=" + password + "\]";  
\}  
\}

controller.java

@RequestMapping(value = "/test11")  
public String test11(Model model)\{

//第一次登录往model注入person  
if(!model.containsAttribute("person"))\{  
model.addAttribute("person", new Person());  
\}  
return "form";  
\}  
  
@RequestMapping(value = "/test12")  
public String test12(@Valid @ModelAttribute(value="person")Person person,  
BindingResult br,Model model)\{  
if(br.hasErrors())\{

//返回登录页面  
return test11(model);  
\}  
System.out.println(person);  
return "hello";  
\}

访问请求：<a href="test11">跳转登录</a>

form.jsp

<%@ page language="java" import="java.util.\*" pageEncoding="UTF-8"%>  
  
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>  
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">  
<html>  
  <head>  
    <title>index.jsp</title>  
<meta http-equiv="pragma" content="no-cache">  
<meta http-equiv="cache-control" content="no-cache">  
<meta http-equiv="expires" content="0">      
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">  
<meta http-equiv="description" content="This is my page">  
  </head>  
    
  <body>  
    <form:form action="test12" method="post" modelAttribute="person">  
    用户名:<form:input path="username"/><form:errors path="username" style="color:red"/><br>  
    密码:<form:input path="password"/><form:errors path="password" style="color:red"/><br>  
    <input type="submit" value="提交"/>  
    </form:form>  
  </body>  
</html>

[http_pan.baidu.com_s_1pKKC4kz]: http://pan.baidu.com/s/1pKKC4kz
[Center]: /images/20220721/4c17c9e63c034059a352bec0bc2629c6.png