高效使用hibernate-validator校验框架
阅读原文时间:2020年09月21日阅读:1

  高效、合理的使用hibernate-validator校验框架可以提高程序的可读性,以及减少不必要的代码逻辑。接下来会介绍一下常用一些使用方式。

限制

说明

@Null

限制只能为null

@NotNull

限制必须不为null

@AssertFalse

限制必须为false

@AssertTrue

限制必须为true

@DecimalMax(value)

限制必须为一个不大于指定值的数字

@DecimalMin(value)

限制必须为一个不小于指定值的数字

@Digits(integer,fraction)

限制必须为一个小数,且整数部分的位数不能超过integer,小数部分的位数不能超过fraction

@Future

限制必须是一个将来的日期

@Max(value)

限制必须为一个不大于指定值的数字

@Min(value)

限制必须为一个不小于指定值的数字

@Past

限制必须是一个过去的日期

@Pattern(value)

限制必须符合指定的正则表达式

@Size(max,min)

限制字符长度必须在min到max之间

@Past

验证注解的元素值(日期类型)比当前时间早

@NotEmpty

验证注解的元素值不为null且不为空(字符串长度不为0、集合大小不为0)

@NotBlank

验证注解的元素值不为空(不为null、去除首位空格后长度为0),不同于@NotEmpty,@NotBlank只应用于字符串且在比较时会去除字符串的空格

@Email

验证注解的元素值是Email,也可以通过正则表达式和flag指定自定义的email格式

public class ValidateGroup {
public interface FirstGroup {
}

public interface SecondeGroup {  
}

public interface ThirdGroup {  
}  

}

@Validated
@GroupSequence({ValidateGroup.FirstGroup.class, BaseMessageRequestBean.class})
public class BaseMessageRequestBean {

//渠道类型  
@NotNull(message = "channelType为NULL", groups = ValidateGroup.FirstGroup.class)  
private String channelType;

//消息(模板消息或者普通消息)  
@NotNull(message = "data为NUll", groups = ValidateGroup.FirstGroup.class)  
@Valid  
private Object data;

//业务类型  
@NotNull(message = "bizType为NULL", groups = ValidateGroup.FirstGroup.class)  
private String bizType;

//消息推送对象  
@NotBlank(message = "toUser为BLANK", groups = ValidateGroup.FirstGroup.class)  
private String toUser;

private long createTime = Instant.now().getEpochSecond();

......  

}

  请自行参考:@Validated和@Valid区别

@RestController
public class TestValidatorController {
@RequestMapping("/test/validator")
public void test(@Validated BaseMessageRequestBean bean){

}
}

  这种使用方式有一个弊端,不能自定义返回异常。spring如果验证失败,则直接抛出异常,一般不可控。

@RestController
public class TestValidatorController {
@RequestMapping("/test/validator")
public void test(@Validated BaseMessageRequestBean bean, BindingResult result){
result.getAllErrors();

}
}

  如果方法中有BindingResult类型的参数,spring校验完成之后会将校验结果传给这个参数。通过BindingResult控制程序抛出自定义类型的异常或者返回不同结果。

  当然了,需要在借助BindingResult的前提下…

@Aspect
@Component
public class ControllerValidatorAspect {
@Around("execution(* com.*.controller..*.*(..)) && args(..,result)")
public Object doAround(ProceedingJoinPoint pjp, result result) {
result.getFieldErrors();

}
}

  这种方式可以减少controller层校验的代码,校验逻辑统一处理,更高效。

@Bean
public Validator validator() {
return new LocalValidatorFactoryBean();
}

LocalValidatorFactoryBean官方示意

  LocalValidatorFactoryBean是Spring应用程序上下文中javax.validation(JSR-303)设置的中心类:它引导javax.validation.ValidationFactory并通过Spring Validator接口以及JSR-303 Validator接口和ValidatorFactory公开它。界面本身。通过Spring或JSR-303 Validator接口与该bean的实例进行通信时,您将与底层ValidatorFactory的默认Validator进行通信。这非常方便,因为您不必在工厂执行另一个调用,假设您几乎总是会使用默认的Validator。这也可以直接注入Validator类型的任何目标依赖项!从Spring 5.0开始,这个类需要Bean Validation 1.1+,特别支持Hibernate Validator 5.x(参见setValidationMessageSource(org.springframework.context.MessageSource))。这个类也与Bean Validation 2.0和Hibernate Validator 6.0运行时兼容,有一个特别说明:如果你想调用BV 2.0的getClockProvider()方法,通过#unwrap(ValidatorFactory.class)获取本机ValidatorFactory,在那里调用返回的本机引用上的getClockProvider()方法。Spring的MVC配置命名空间也使用此类,如果存在javax.validation API但未配置显式Validator。

@Component
public class ValidatorUtils implements ApplicationContextAware {

@Override  
public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {  
    **ValidatorUtils.validator** **\= (Validator) applicationContext.getBean("validator"****);**  
}

private static Validator validator;

public static Optional<String> validateResultProcess(Object obj)  {  
    Set<ConstraintViolation<Object>> results = validator.validate(obj);  
    if (CollectionUtils.isEmpty(results)) {  
        return Optional.empty();  
    }  
    StringBuilder sb = new StringBuilder();

    for (Iterator<ConstraintViolation<Object>> iterator = results.iterator(); iterator.hasNext(); ) {  
        sb.append(iterator.next().getMessage());  
        if (iterator.hasNext()) {  
            sb.append(" ,");  
        }  
    }  
    return Optional.of(sb.toString());  
}  

}

  为什么要使用这个工具类呢?

  1、controller方法中不用加入BindingResult参数

  2、controller方法中需要校验的参数也不需要加入@Valid或者@Validated注解

  怎么样是不是又省去了好多代码,开不开心。

  具体使用,在controller方法或者全局拦截校验器中调用 ValidatorUtils.validateResultProcess(需要校验的Bean) 直接获取校验的结果。

  请参考更多功能的ValidatorUtils工具类

  定义一个MessageRequestBean,继承BaseMessageRequestBean,signature字段需要我们自定义校验逻辑。

@Validated
@GroupSequence({ValidateGroup.FirstGroup.class, ValidateGroup.SecondeGroup.class, MessageRequestBean.class})
@LogicValidate(groups = ValidateGroup.SecondeGroup.class)
public class MessageRequestBean extends BaseMessageRequestBean {

//签名信息(除该字段外的其他字段按照字典序排序,将值顺序拼接在一起,进行md5+Base64签名算法)  
@NotBlank(message = "signature为BLANK", groups = ValidateGroup.FirstGroup.class)  
private String signature;  
...  

}

  实现自定义校验逻辑也很简单……

  1、自定义一个带有 @Constraint注解的注解@LogicValidate,validatedBy 属性指向该注解对应的自定义校验器

@Target({TYPE})
@Retention(RUNTIME)
//指定验证器
@Constraint(validatedBy = LogicValidator.class)
@Documented
public @interface LogicValidate {
String message() default "校验异常";
//分组
Class[] groups() default {};
Class[] payload() default {};
}

  2、自定义校验器LogicValidator,泛型要关联上自定义的注解和需要校验bean的类型

public class LogicValidator implements ConstraintValidator {

@Override  
public void initialize(LogicValidate logicValidate) {  
}

@Override  
public boolean isValid(MessageRequestBean messageRequestBean, ConstraintValidatorContext context) {  
    String toSignature = StringUtils.join( messageRequestBean.getBizType()  
            , messageRequestBean.getChannelType()  
            , messageRequestBean.getData()  
            , messageRequestBean.getToUser());  
    String signature = new Base64().encodeAsString(DigestUtils.md5(toSignature));  
    if (!messageRequestBean.getSignature().equals(signature)) {  
        **context.disableDefaultConstraintViolation();  
        context.buildConstraintViolationWithTemplate(****"signature校验失败")  
                .addConstraintViolation();** return false;  
    }  
    return true;  
}  

}

  可以通过ConstraintValidatorContext禁用掉默认的校验配置,然后自定义校验配置,比如校验失败后返回的信息。

@Configuration
@ConditionalOnMissingBean(value = MessageSource.class, search = SearchStrategy.CURRENT)
@AutoConfigureOrder(Ordered.HIGHEST_PRECEDENCE)
@Conditional(ResourceBundleCondition.class)
@EnableConfigurationProperties
@ConfigurationProperties(prefix = "spring.messages")
public class MessageSourceAutoConfiguration {

private static final Resource\[\] NO\_RESOURCES = {};

/\*\*  
 \* Comma-separated list of basenames, each following the ResourceBundle convention.  
 \* Essentially a fully-qualified classpath location. If it doesn't contain a package  
 \* qualifier (such as "org.mypackage"), it will be resolved from the classpath root.  
 \*/  
private String basename = "messages";

/\*\*  
 \* Message bundles encoding.  
 \*/  
private Charset encoding = Charset.forName("UTF-8");

/\*\*  
 \* Loaded resource bundle files cache expiration, in seconds. When set to -1, bundles  
 \* are cached forever.  
 \*/  
private int cacheSeconds = -1;

/\*\*  
 \* Set whether to fall back to the system Locale if no files for a specific Locale  
 \* have been found. if this is turned off, the only fallback will be the default file  
 \* (e.g. "messages.properties" for basename "messages").  
 \*/  
private boolean fallbackToSystemLocale = true;

/\*\*  
 \* Set whether to always apply the MessageFormat rules, parsing even messages without  
 \* arguments.  
 \*/  
private boolean alwaysUseMessageFormat = false;

@Bean  
public MessageSource messageSource() {  
    ResourceBundleMessageSource messageSource = new ResourceBundleMessageSource();  
    if (StringUtils.hasText(this.basename)) {  
        messageSource.setBasenames(StringUtils.commaDelimitedListToStringArray(  
                StringUtils.trimAllWhitespace(this.basename)));  
    }  
    if (this.encoding != null) {  
        messageSource.setDefaultEncoding(this.encoding.name());  
    }  
    messageSource.setFallbackToSystemLocale(this.fallbackToSystemLocale);  
    messageSource.setCacheSeconds(this.cacheSeconds);  
    messageSource.setAlwaysUseMessageFormat(this.alwaysUseMessageFormat);  
    return messageSource;  
}

public String getBasename() {  
    return this.basename;  
}

public void setBasename(String basename) {  
    this.basename = basename;  
}

public Charset getEncoding() {  
    return this.encoding;  
}

public void setEncoding(Charset encoding) {  
    this.encoding = encoding;  
}

public int getCacheSeconds() {  
    return this.cacheSeconds;  
}

public void setCacheSeconds(int cacheSeconds) {  
    this.cacheSeconds = cacheSeconds;  
}

public boolean isFallbackToSystemLocale() {  
    return this.fallbackToSystemLocale;  
}

public void setFallbackToSystemLocale(boolean fallbackToSystemLocale) {  
    this.fallbackToSystemLocale = fallbackToSystemLocale;  
}

public boolean isAlwaysUseMessageFormat() {  
    return this.alwaysUseMessageFormat;  
}

public void setAlwaysUseMessageFormat(boolean alwaysUseMessageFormat) {  
    this.alwaysUseMessageFormat = alwaysUseMessageFormat;  
}

protected static class ResourceBundleCondition extends SpringBootCondition {

    private static ConcurrentReferenceHashMap<String, ConditionOutcome> cache = new ConcurrentReferenceHashMap<String, ConditionOutcome>();

    @Override  
    public ConditionOutcome getMatchOutcome(ConditionContext context,  
            AnnotatedTypeMetadata metadata) {  
        String basename = context.getEnvironment()  
                .getProperty("spring.messages.basename", "messages");  
        ConditionOutcome outcome = cache.get(basename);  
        if (outcome == null) {  
            outcome = getMatchOutcomeForBasename(context, basename);  
            cache.put(basename, outcome);  
        }  
        return outcome;  
    }

    private ConditionOutcome getMatchOutcomeForBasename(ConditionContext context,  
            String basename) {  
        ConditionMessage.Builder message = ConditionMessage  
                .forCondition("ResourceBundle");  
        for (String name : StringUtils.commaDelimitedListToStringArray(  
                StringUtils.trimAllWhitespace(basename))) {  
            for (Resource resource : getResources(context.getClassLoader(), name)) {  
                if (resource.exists()) {  
                    return ConditionOutcome  
                            .match(message.found("bundle").items(resource));  
                }  
            }  
        }  
        return ConditionOutcome.noMatch(  
                message.didNotFind("bundle with basename " + basename).atAll());  
    }

    private Resource\[\] getResources(ClassLoader classLoader, String name) {  
        try {  
            return new PathMatchingResourcePatternResolver(classLoader)  
                    .getResources("classpath\*:" + name + ".properties");  
        }  
        catch (Exception ex) {  
            return NO\_RESOURCES;  
        }  
    }

}

}

  从上面的MessageSource自动配置可以看出,可以通过spring.message.basename指定要配置国际化文件位置,默认值是“message”。spring boot默认就支持国际化的,默认会去resouces目录下寻找message.properties文件。

  这里就不进行过多关于国际化相关信息的介绍了,肯定少不了区域解析器。springboot国际化相关知识请参考:Spring Boot国际化(i18n)