自定義數據校驗註解

給初學者分享一下利用反射加AOP做的自定義註解，用來數據校驗挺不錯的，自己用着玩的

1.自定義註解

 * 註解驗證
 *
 * @author syliu
 * @create 2017/10/31 0031
 */
@Retention(RetentionPolicy.RUNTIME)
@Target({ ElementType.METHOD, ElementType.TYPE })
@Documented
public @interface ValidAnnotations {
		String[] target() default {};
}

2.自定義攔截器

package com.syliu.waiting.common.domain;

import com.syliu.waiting.common.exception.GlobalException;
import lombok.val;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Before;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;

import java.lang.reflect.Method;
import java.util.Map;

/**
 *
 * @author syliu
 */
@Aspect
@Component
public class ValidSecureAspect {
	public final static Logger log = LoggerFactory.getLogger(ValidSecureAspect.class);
	@Before("@annotation(nonEmpty)")
	public void  validSecure(JoinPoint point, ValidAnnotations nonEmpty){
		//獲取註解的參數
		String[] target = nonEmpty.target();
		//如果註解參數不爲空
		if (!StringUtils.isEmpty(target)){
			//獲取入參
			Object[] args = point.getArgs();
			if (!StringUtils.isEmpty(args)){
				val arg = args[0];
				checkField(arg,target);
			}else {
				throw new GlobalException("參數爲空",-1);
			}
		}
	}
	public void checkField(Object object,String[] target){
		if(StringUtils.isEmpty(object)){
			throw new GlobalException("參數爲空",-1);
		}
		//獲取類型名稱
		final String typeName = object.getClass().getTypeName();
			if (Map.class.getTypeName().equals(typeName)){
				Map map=(Map)object;
				//循環取值，從map中獲取value
				for (String targets : target) {
					Object o = map.get(target);
					if (StringUtils.isEmpty(o)){
						throw new GlobalException(targets+":is Empty",-1);
					}
				}
			}else if (Object.class.getTypeName().equals(typeName)){
				for (String name: target) {
					final Object fieldValue = getFieldValue(object, name);
					if (StringUtils.isEmpty(fieldValue)){
						throw new GlobalException(name+":is Empty",-1);
					}
				}
			}else if (typeName.startsWith("com.syliu")){
				for (String name: target) {
					final Object fieldValue = getFieldValue(object, name);
					if (StringUtils.isEmpty(fieldValue)){
						throw new GlobalException(name+":is Empty",-1);
					}
				}
			}
	}
	public Object getFieldValue(Object object,String name){
		Object value=null;
		if(!StringUtils.isEmpty(name)){
			String upperName = name.substring(0, 1).toUpperCase()
					+ name.substring(1);
			try {
				Method method=object.getClass()
						.getMethod("get" + upperName);
				value = method.invoke(object);
			} catch (Exception e) {
			}
		}
		return value;
	}
}

3.用法

	@ValidAnnotations(target ={"password","username"})
	@Override
	public Result reg(UserEntity userEntity) {
		String username = userEntity.getUsername();
		UserEntity user=userRepository.findByUsername(username);
		if (StringUtils.isEmpty(user)){
			UserEntity save = userRepository.save(userEntity);
			return new Result(getUserInfo(save));
		}
		throw new GlobalException(ResultEnum.USER_HASED);
	}