如何在object字段上方获取@size注释的值

Question

我需要从@size注释中提取属性值

private static int getMaxLimitSize(Field field){

    field.setAccessible(true);
    Size annotation = field.getAnnotation(Size.class);

    int zero = 0;

    if(annotation == null) return zero;

    return annotation.max();

}

下面是dto类型对象字段上的@size约束

 @Size(message = "{validate.documentid.size}", max = 36)
private String documentId;

Size annotation = null;

@Configuration
public class ServiceConfig implements WebMvcConfigurer {



    @Bean
    public MessageSource messageSource() {
        ResourceBundleMessageSource source = new ResourceBundleMessageSource();
        source.setDefaultEncoding("UTF-8");
        source.setBasename("classpath:ValidationMessages");
        return source;
    }

    @Nullable
    @Override
    public Validator getValidator() {
        LocalValidatorFactoryBean validator = new LocalValidatorFactoryBean();
        validator.setValidationMessageSource(messageSource());
        return validator;
    }

}

private static void processLimitValidateForField(Field field, Object object, List<Object> values){

    Class<?> type = field.getType();
    String typeName = type.getSimpleName();

    boolean isTypeClassOfString = isStringType(typeName);

    int limitString = 0;

    if(isTypeClassOfString){
        limitString = getMaxLimitSize(field);
        setValue(field, typeName, object, values, limitString);
    } else {
        setValue(field, typeName, object, values, limitString);
    }
}

Answer 1

您可以通过调用方法字段#get(currentObject)来获取字段值

if (field.isAccessible()) {
    Object someValue = field.get(object);
}