Spring 自己实现注解数据验证

╰半橙微兮° 2022-06-17 12:17 214阅读 0赞

# [\[Spring MVC\] - Annotation验证][Spring MVC_ - Annotation] #

使用Spring MVC的Annotation验证可以直接对view model的简单数据验证，注意，这里是简单的，如果model的数据验证需要有一些比较复杂的业务逻辑性在里头，只是使用annotation做验证是比较难的。

以下是使用Spring MVC自带的annotation验证，加上自定义的一个@Tel的annotation验证例子，此例子具有：

1、支持多语言（国际化）

2、对默认数据先进行转化，比如int、date类型如果传入空值时，会抛异常，默认给定值

--------------------

先看配置：

1、web.xml

![复制代码][copycode.gif]

<?xml version="1.0" encoding="UTF-8"?>
 <web-app version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
 xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
 http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd">
 <display-name>Test Spring MVC - 1</display-name>
 
 <context-param>
 <param-name>contextConfigLocation</param-name>
 <param-value>classpath:spring.xml</param-value>
 </context-param>
 <servlet>
 <servlet-name>dispatcher</servlet-name>
 <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
 <init-param>
 <param-name>contextConfigLocation</param-name>
 <param-value></param-value>
 </init-param>
 <load-on-startup>1</load-on-startup>
 </servlet>
 <servlet-mapping>
 <servlet-name>dispatcher</servlet-name>
 <url-pattern>/</url-pattern>
 </servlet-mapping>
 <listener>
 <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
 </listener>
 
 <welcome-file-list>
 <welcome-file>index.jsp</welcome-file>
 </welcome-file-list>
 
 </web-app>

![复制代码][copycode.gif]

这里没什么好说的，只是把spring.xml配置加入到contextConfigLocation中

2、spring.xml

![复制代码][copycode.gif]

<?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:tx="http://www.springframework.org/schema/tx"
 xmlns:context="http://www.springframework.org/schema/context" 
 xmlns:mvc="http://www.springframework.org/schema/mvc" 
 xsi:schemaLocation="http://www.springframework.org/schema/beans 
 http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
 http://www.springframework.org/schema/tx 
 http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
 http://www.springframework.org/schema/context
 http://www.springframework.org/schema/context/spring-context-3.0.xsd
 http://www.springframework.org/schema/mvc
 http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
 
 
 <context:annotation-config />
 
 
 <mvc:annotation-driven validator="validator" conversion-service="conversionService" />
 
 
 <context:component-scan base-package="com.my" />
 
 
 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
 <property name="prefix" value="/WEB-INF/views/"/>
 <property name="suffix" value=".jsp"/>
 <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
 </bean>
 
 
 <bean id="messageSource" class="org.springframework.context.support.ResourceBundleMessageSource">
 <property name="basenames">
 <list>
 <value>messages</value>
 </list>
 </property>
 </bean>
 
 <bean id="validator" class="org.springframework.validation.beanvalidation.LocalValidatorFactoryBean">
 <property name="validationMessageSource" ref="messageSource"/>
 </bean>
 
 
 <bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
 <property name="converters">
 <list>
 <bean class="com.my.controller.converter.IntConverter" />
 <bean class="com.my.controller.converter.DateConverter" />
 </list>
 </property>
 </bean>
 
 </beans>

![复制代码][copycode.gif]

在<mvc:annotation-driven/>中加入conversion-service，然后在conversion-service中加入系统默认的转换器，如上有IntConverter和DateConverter，当然，也可以是自定的别的类型，这是全局的。

在validator验证器中加入了支持多语言的properties，当然，spring的多语言是基于http header的accept-language。

3、Controller

![复制代码][copycode.gif]

package com.my.controller;
 
 import java.util.List;
 
 import javax.validation.Valid;
 
 import org.springframework.stereotype.Controller;
 import org.springframework.validation.BindingResult;
 import org.springframework.validation.FieldError;
 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.my.controller.bean.User4;
 
 @Controller
 @RequestMapping(value="av")
 public class TestAnnotationValidController {
 
 @RequestMapping
 public ModelAndView index() {
 ModelAndView view = new ModelAndView("/TestAnnotationValid/index", "user4", new User4());
 return view;
 }
 
 @RequestMapping(value="/add", method=RequestMethod.POST)
 public ModelAndView add(@ModelAttribute @Valid User4 user, BindingResult result) {
 ModelAndView view = new ModelAndView("/TestAnnotationValid/index");
 view.addObject("user4", user);
 
 if(result.hasErrors()) {
 List<FieldError> errors = result.getFieldErrors();
 for(FieldError err : errors) {
 System.out.println("ObjectName:" + err.getObjectName() + "\tFieldName:" + err.getField()
 + "\tFieldValue:" + err.getRejectedValue() + "\tMessage:" + err.getDefaultMessage() + "\tCode:");
 }
 }
 
 return view;
 }
 
 }

![复制代码][copycode.gif]

这是一个简单的controller，在add中，有一个@Valid的annotation，这是必需的，不加这个，annotation验证将不起作用

4、User4.java model实体类

![复制代码][copycode.gif]

package com.my.controller.bean;
    
    import java.util.Date;
    
    import javax.validation.constraints.Max;
    import javax.validation.constraints.Min;
    import javax.validation.constraints.NotNull;
    import javax.validation.constraints.Past;
    import javax.validation.constraints.Pattern;
    import javax.validation.constraints.Size;
    
    import org.hibernate.validator.constraints.Email;
    import org.hibernate.validator.constraints.Length;
    import org.hibernate.validator.constraints.NotBlank;
    
    public class User4 {
        
        private long id;
        
        @NotBlank(message="{valid.name}")
        private String name;
        
        @Length(min=4, max=20, message="{valid.password}")
        private String password;
        
        @NotBlank(message="{valid.required}")
        @Email(message="{valid.email}")
        private String email;
        
        @NotNull(message="{valid.required}")
        private boolean married;
        
        @Min(value=18, message="{valid.ageMin}")
        @Max(value=100, message="{valid.ageMax}")
        private int age;
        
        @NotNull(message="{valid.required}")
        @Past(message="{valid.birthday}")
        private Date birthday;
        
        @Pattern(regexp="^[a-zA-Z]{2,}$", message="{valid.address}")
        private String address;
        
        @Size(min=1, message="{valid.likesMin}")
        private String[] likes;
        
        @com.my.controller.validator.Tel(message="{valid.tel}", min=3)
        private String tel;
        
        public long getId() {
            return id;
        }
        public void setId(long id) {
            this.id = id;
        }
        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 boolean isMarried() {
            return married;
        }
        public void setMarried(boolean married) {
            this.married = married;
        }
        public int getAge() {
            return age;
        }
        public void setAge(int age) {
            this.age = age;
        }
        public Date getBirthday() {
            return birthday;
        }
        public void setBirthday(Date birthday) {
            this.birthday = birthday;
        }
        public String getAddress() {
            return address;
        }
        public void setAddress(String address) {
            this.address = address;
        }
        public String[] getLikes() {
            return likes;
        }
        public void setLikes(String[] likes) {
            this.likes = likes;
        }
        public String getTel() {
            return tel;
        }
        public void setTel(String tel) {
            this.tel = tel;
        }
    
    }

![复制代码][copycode.gif]

除了@Tel之外，其它都是spring自带的annotation，当然还有别的，自行搜索下

5、message.properties

![复制代码][copycode.gif]

valid.required=字段值不能为空
    valid.name=用户名不能为空
    valid.password=密码最小4位
    valid.ageMin=年龄不能小于{
         1}岁
    valid.ageMax=年龄不能大于{
         1}岁
    valid.email=邮箱格式不正确
    valid.address=联系地址不正确
    valid.birthday=生日不能大于今天
    valid.likesMin=喜好最小不能小于1个
    valid.tel=手机号码不能小于{min}位

![复制代码][copycode.gif]

对应的是User4 model的annotation的message值。如果需要国际化的多语言，只需要加入多一个messages\_en\_US.properties这样名字的文件即可。

6、@Tel

![复制代码][copycode.gif]

package com.my.controller.validator;
 
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 import javax.validation.Constraint;
 import javax.validation.Payload;
 
 @Target({ElementType.FIELD, ElementType.METHOD})
 @Retention(RetentionPolicy.RUNTIME)
 @Constraint(validatedBy=TelValidator.class)
 public @interface Tel {
 
 int min() default 0;
 
 String message();
 
 Class<?>[] groups() default {};
 
 Class<? extends Payload>[] payload() default {};
 
 }

![复制代码][copycode.gif]

新建一个interface，注意，annotation的interface java是这样写的：@interface

TelValidator:

![复制代码][copycode.gif]

package com.my.controller.validator;
 
 import javax.annotation.Resource;
 import javax.validation.ConstraintValidator;
 import javax.validation.ConstraintValidatorContext;
 
 import org.springframework.context.support.ResourceBundleMessageSource;
 
 public class TelValidator implements ConstraintValidator<Tel, String> {
 
 @Resource
 private ResourceBundleMessageSource messageSource;
 
 private Tel tel;
 
 @Override
 public void initialize(Tel tel) {
 this.tel = tel;
 }
 
 @Override
 public boolean isValid(String value, ConstraintValidatorContext constraintContext) {
 boolean isValid;
 
 if(value != null && value.length() >= tel.min()) {
 isValid = true;
 }
 else {
 isValid = false;
 }
 
 if(!isValid) {
 constraintContext.disableDefaultConstraintViolation();
 constraintContext.buildConstraintViolationWithTemplate(tel.message()).addConstraintViolation();
 }
 return isValid;
 }
 
 }

![复制代码][copycode.gif]

这是@Tel的验证实现方法。

7、Converter

![复制代码][copycode.gif]

package com.my.controller.converter;
 
 import org.springframework.core.convert.converter.Converter;
 
 public class IntConverter implements Converter<String, Integer> {
 
 @Override
 public Integer convert(String text) {
 if (text == null || "".equals(text)) {
 return 0;
 } else {
 try {
 Integer value = Integer.parseInt(text);
 return value;
 } catch (Exception e) {
 return 0;
 }
 }
 }
 
 }

![复制代码][copycode.gif]

package com.my.controller.converter;
 
 import java.text.ParseException;
 import java.text.SimpleDateFormat;
 import java.util.Date;
 
 import org.springframework.core.convert.converter.Converter;
 
 public class DateConverter implements Converter<String, Date> {
 
 @Override
 public Date convert(String text) {
 SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
 dateFormat.setLenient(false);
 try {
 return dateFormat.parse(text);
 } catch (ParseException e) {
 e.printStackTrace();
 }
 return null;
 }
 
 }

![复制代码][copycode.gif]

这两个是全局的类型默认转换器。

8、测试JSP

![复制代码][copycode.gif]

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 
 <%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt"%>
 <%@ taglib uri="http://java.sun.com/jsp/jstl/functions" prefix="fn" %>
 <%@ taglib prefix="st" uri="http://www.springframework.org/tags" %>
 <%@ 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>Index</title>
 </head>
 <body>
 <sf:form action="${pageContext.request.contextPath}/av/add" method="post" modelAttribute="user4">
 User name:<sf:input path="name"/><sf:errors path="name" /> 
 Password:<sf:input path="password"/><sf:errors path="password" /> 
 E-mail:<sf:input path="email"/><sf:errors path="email" /> 
 Age:<sf:input path="age"/><sf:errors path="age" /> 
 Birthday:<sf:input path="birthday"/><sf:errors path="birthday" /> 
 Address:<sf:input path="address"/><sf:errors path="address" /> 
 Married:
 <sf:radiobutton path="married" label="Yes" value="true"/>
 <sf:radiobutton path="married" label="No" value="false"/>
 <sf:errors path="married" /> 
 Likes:
 <sf:checkbox path="likes" label="Football" value="Football"/>
 <sf:checkbox path="likes" label="Badminton" value="Badminton"/>
 <sf:checkbox path="likes" label="Pingpong" value="Pingpong"/>
 <sf:errors path="likes" /> 
 Tel:<sf:input path="tel"/><sf:errors path="tel" /> 
 <input type="submit" value="Add" />
 <hr/>
 Errors: <sf:errors path="*"></sf:errors>
 <hr/>
 Likes:<c:forEach items="${user4.likes}" var="item">${item},</c:forEach>
 </sf:form>
 </body>
 </html>

![复制代码][copycode.gif]

注意，在form中的modelAttribute属性值，它对应的是User4类名，小写开头，否则会出错

9、页面UI结果：

![261412261687780.png][]

点击Add button后：

![261413104023135.png][]

[Spring MVC_ - Annotation]: http://www.cnblogs.com/HD/p/4123146.html
[copycode.gif]: /images/20220617/f5da8fcc155741d09b46e59c9043c62a.png
[261412261687780.png]: /images/20220617/a88c60b9e61741a0a773d2d394e5f85e.png
[261413104023135.png]: /images/20220617/30651b43ab2348cbbf42f5e466b1cc2b.png