spring mvc的errors标签和validator用法

最新推荐文章于 2023-07-20 16:18:11 发布

转载最新推荐文章于 2023-07-20 16:18:11 发布 · 319 阅读

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CC 4.0 BY-SA版权

原文链接：https://yq.aliyun.com/articles/431502

文章标签：

#java #测试 #web.xml

本文介绍了一个基于Spring MVC框架的简单用户注册示例，包括用户表单验证、控制器处理及视图展示等内容。该示例展示了如何创建User类、实现UserValidator验证器并将其应用于UserController中。

通过示例学习，

然后举一返三，

是最快的吸收知识的方式。

web.xml和springmvc-config.xml文件的内容同前面。

这一系列使用eclipse建立java项目时，选择动态web项目即可。

User.java

package org.fkit.domain;

import java.io.Serializable;

public class User implements Serializable {
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	private String username;
	private String sex;
	private Integer age;
	
	public User() {
		super();
	}
	public User(String username, String sex, Integer age) {
		super();
		this.username = username;
		this.sex = sex;
		this.age = age;
	}
	public String getUsername() {
		return username;
	}
	public void setUsername(String username) {
		this.username = username;
	}
	public String getSex() {
		return sex;
	}
	public void setSex(String sex) {
		this.sex = sex;
	}
	public Integer getAge() {
		return age;
	}
	public void setAge(Integer age) {
		this.age = age;
	}
	

	

}

UserValidator.java

package org.fkit.validator;


import org.fkit.domain.User;
import org.springframework.validation.Errors;
import org.springframework.validation.ValidationUtils;
import org.springframework.validation.Validator;


public class UserValidator implements Validator {
	
	@Override
	public boolean supports(Class<?> clazz) {
		return User.class.equals(clazz);
	}
	
	@Override
	public void validate(Object object, Errors errors) {
		ValidationUtils.rejectIfEmpty(errors, "username", null, "用户名不能为空");
		ValidationUtils.rejectIfEmpty(errors, "sex", null, "性别不能为空");
		ValidationUtils.rejectIfEmpty(errors, "age", null, "年龄不能为空");
	}

}

UserController.java

package org.fkit.controller;




import org.fkit.domain.User;
import org.fkit.validator.UserValidator;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.validation.DataBinder;
import org.springframework.validation.Errors;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;


@Controller

public class UserController {
	@RequestMapping(value="/registerForm", method=RequestMethod.GET)
	public String registerForm(Model model) {
		User user = new User();
		model.addAttribute("user", user);

		return "registerForm";
	}
	
	@InitBinder
	public void initBinder(WebDataBinder binder) {
		binder.setValidator(new UserValidator());
	}
	
	@RequestMapping(value="/register", method=RequestMethod.POST)
	public String register(@Validated User user, Errors errors) {
		if (errors.hasFieldErrors()) 
			return "registerForm";
		return "helloWorld";
	}
	
}

registerForm.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %>
<%@ taglib prefix="form" 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 content="text/html; charset=UTF-8" http-equiv="Content-Type">
	<title>welcome</title>
</head>
<body>

<h3>注册页面</h3>
<br>
<form:form modelAttribute="user" action="register" method="post">
	<table>
	<tr>
		<td><label>姓名: </label></td>
		<td><form:input path="username"/></td>
		<td><font color="red"><form:errors path="username" /></font></td>
	</tr>
	<tr>
		<td><label>性别: </label></td>
		<td><form:input path="sex"/></td>
		<td><font color="red"><form:errors path="sex" /></font></td>
	</tr>
	<tr>
		<td><label>年龄: </label></td>
		<td><form:input path="age"/></td>
		<td><font color="red"><form:errors path="age" /></font></td>
	</tr>
	<tr>
		<td><input id="submit" type="submit" value="register"></td>
	</tr>
	
	</table>

</form:form>

</body>
</html>

测试：

12119bb37c05d6c557bcbca2d7242e09f652d337