简易Java注解自动validate工具

对应Java后端开发来说，Hibernate Validator参数自动化校验非常熟悉了，结合Spring Aop在接口入参自动校验功能非常强大，可配置的校验规则也非常多。不过在一些体量不是那么大的项目里，业务规则也不是特别复杂，结合Java注解，实现了一个非常简易的入参校验工具。主要包含了参数规则注解定义，以及校验逻辑实现两部分。

• 规则注解定义Rule

  @Target({ ElementType.TYPE, ElementType.FIELD })
  @Retention(RetentionPolicy.RUNTIME)
  @Repeatable(ParamRules.class)
  public @interface Rule {
  
  	/**
  	 * 业务场景即分组名称
  	 * 
  	 * @return
  	 */
  	String group() default "";
  
  	/**
  	 * 是否为空标签
  	 * 
  	 * @return
  	 */
  	NotNull notNull() default @NotNull;
  
  	/**
  	 * 字段长度
  	 * 
  	 * @return
  	 */
  	Length len() default @Length;
  
  	/**
  	 * 长度范围
  	 * 
  	 * @return
  	 */
  	Size size() default @Size;
  
  	/**
  	 * 区间
  	 * 
  	 * @return
  	 */
  	Rang rang() default @Rang;
  
  	/**
  	 * 字段校验规则，正则表达式
  	 * 
  	 * @return
  	 */
  	Regex regex() default @Regex;
  }
  

  将每个单独的规则另外定义为注解。

• NotNull

@Target(ElementType.ANNOTATION_TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface NotNull {

	String message() default "";

}

• Length

@Target(ElementType.ANNOTATION_TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface Length {

	int length() default 0;

	String message() default "";

}

• Size

@Target(ElementType.ANNOTATION_TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface Size {

	String message() default "";
	
	int min() default 0;
	
	int max() default Integer.MAX_VALUE;
	
}

• Range

@Target(ElementType.ANNOTATION_TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface Rang {

	String message() default "";

	int min() default 0;

	int max() default Integer.MAX_VALUE;
}

• Regex

  @Target(ElementType.ANNOTATION_TYPE)
  @Retention(RetentionPolicy.RUNTIME)
  public @interface Regex {
  
  	String message() default "";
  	
  	String regex() default "";
  	
  }
  

  校验逻辑处理类ParamChecker

  
  	
  	/** class类型中所有被Rule注解的属性列表*/
  	private static ConcurrentHashMap, List> ruledFileds = new ConcurrentHashMap<>();
  	
  	private static ConcurrentHashMap> fieldRules = new ConcurrentHashMap<>();
  
  	public static List checkParam(Object param, String group) {
  		List messages = new ArrayList<>();
  		String paramError;
  		if (param == null) {
  			paramError = "入参为空";
  			log.error(paramError);
  			messages.add(paramError);
  			return messages;
  		}
  		Class paramClazz = param.getClass();
  		List fields = ruledFileds.get(paramClazz);
  		if(fields == null) {
  			List allFields = FieldUtil.getAllFields(paramClazz);
  			fields = allFields.stream().filter(e -> {
  				Rule[] annotationsByType = e.getAnnotationsByType(Rule.class);
  				if(annotationsByType.length == 0) {
  					return false;
  				}
  				fieldRules.put(e, Arrays.asList(annotationsByType));
  				return true;
  			}).collect(Collectors.toList());
  		}
  		ruledFileds.put(paramClazz, fields);
  		BeanMap beanMap = ToString.getBeanMap(param);
  		// 遍历属性，校验规则
  		for(Field field : fields) {
  			Object value = beanMap.get(field.getName());
  			// 获取field上的rule注解信息
  			List ruleList = fieldRules.get(field);
  			Rule rule = null;
  			// 有多个规则分组
  			if(ruleList.size() > 1) {
  				for(Rule r : ruleList) {
  					String multiGroup = r.group();
  					// 取默认分组
  					if(group == null) {
  						if("".equals(multiGroup)) {
  							rule = r;
  							break;
  						}
  					} else {
  						if(group.equals(multiGroup)) {
  							rule = r;
  							break;
  						}
  					}
  					
  				}
  			} else {
  				rule = ruleList.get(0);
  			}
  			if(rule != null) {
  				// 非空判断
  				NotNull notNull = rule.notNull();
  				String notMsg = notNull.message();
  				if(value == null && !"".equals(notMsg)) {
  					messages.add(notMsg);
  				}
  				// 字段长度
  				Length len = rule.len();
  				String lenMsg = len.message();
  				if(value != null && !"".equals(lenMsg)) {
  					int valueLen = value.toString().length();
  					if(valueLen != len.length()) {
  						messages.add(lenMsg);
  					}
  				}
  				// 字段长度范围
  				Size size = rule.size();
  				String sizeMsg = size.message();
  				if(value != null && !"".equals(sizeMsg)) {
  					int valueLen = value.toString().length();
  					if(valueLen < size.min() || valueLen > size.max()) {
  						messages.add(sizeMsg);
  					}
  				}
  				// 区间
  				Rang rang = rule.rang();
  				String rangMsg = rang.message();
  				if(value != null && !"".equals(rangMsg)) {
  					int valueInt = Integer.parseInt(value.toString());
  					if(valueInt < rang.min() || valueInt > rang.max()) {
  						messages.add(rangMsg);
  					}
  				}
  				// 正则
  				Regex regex = rule.regex();
  				String regMsg = regex.message();
  				if(value != null && !"".equals(regMsg)) {
  					String valueStr = value.toString();
  					if(!valueStr.matches(regex.regex())) {
  						messages.add(regMsg);
  					}
  				}
  			}
  		}
  		return messages;
  		
  	}
  
  	public static void main(String[] args) {
  		ParamA param = new ParamA();
  		param.setName("Lydcka");
  		param.setAge(28);
  		param.setPhone("188115882474");
  		List checkParam = checkParam(param, "create");
  		//-----------
  		param.setName(null);
  		log.info(checkParam.toString());
  		List checkParam2 = checkParam(param, null);
  		log.info(checkParam2.toString());
  		//-----------
  		param.setName("Lydckaasdf");
  		List checkParam3 = checkParam(param, "create");
  		log.info(checkParam3.toString());
  	}
  

  标记入参对象

  
  @Data
  public class ParamA {
  
  	@Rule(notNull = @NotNull(message = "name 不能为空"))
  	@Rule(group = "create", notNull = @NotNull(message = "name 不能为空"), len = @Length(length = 6, message = "name 长度为6"))
  	private String name;
  
  	@Rule(rang = @Rang(min = 1, max = 120, message = "age 年龄区间为1-120岁之间"))
  	private int age;
  
  	@Rule(regex = @Regex(regex = "1([38][0-9]|4[579]|5[0-3,5-9]|6[6]|7[0135678]|9[89])\\d{8}", message = "phone 手机号格式不正确"))
  	private String phone;
  }
  

   

• 自此，简易入参自动校验完成

  16:54:10.441 [main] INFO comm.param.ParamChecker - [phone 手机号格式不正确]
  16:54:10.460 [main] INFO comm.param.ParamChecker - [name 不能为空, phone 手机号格式不正确]
  16:54:10.461 [main] INFO comm.param.ParamChecker - [name 长度为6, phone 手机号格式不正确]