结合spring 实现自定义注解

注解类

import java.lang.annotation.*;

/**
 * Created by Administrator on 2016/6/28.
 */
//ElementType.METHOD 在方法上使用
@Target(ElementType.METHOD)
//范围
@Retention(RetentionPolicy.RUNTIME)
@Documented
public @interface Cacheable {

    String key();
    String fieldKey() ;
    int expireTime() default 1800000;
}

　注解实现类

@Aspect
public class CacheAspect {

    private Logger logger = LoggerFactory.getLogger(CacheAspect.class);

    public CacheAspect(){
    }


    @Pointcut(value = "execution(@Cacheable * *.*(..))")
    public void setCacheRedis(){}

    /**
     * aop实现自定缓存注解
     *
     * @param joinPoint
     * @return
     */

    //@Around("@annotation(com.manage.annotations.Cacheable)")  不知道为什么这么写不行
　　//这个里面的值要上面的方法名一致
    @Around("setCacheRedis()")
    public Object setCache(ProceedingJoinPoint joinPoint) {
        Object result = null;

        Method method = getMethod(joinPoint);

　　　　　//自定义注解类
        Cacheable cacheable = method.getAnnotation(Cacheable.class);
　　　　　//获取key值　
　　　　　String key = cacheable.key();
　　　　　String fieldKey=cacheable.fieldKey();
　　　　　　 　
        //获取方法的返回类型,让缓存可以返回正确的类型
        Class returnType=((MethodSignature)joinPoint.getSignature()).getReturnType();
　　　　
　　　　　下面就是根据业务来自行操作　
        return result;
    }
public Method getMethod(ProceedingJoinPoint pjp) {
        //获取参数的类型
        Object[] args = pjp.getArgs();
        Class[] argTypes = new Class[pjp.getArgs().length];
        for (int i = 0; i < args.length; i++) {
            argTypes[i] = args[i].getClass();
        }
        Method method = null;
        try {
            method = pjp.getTarget().getClass().getMethod(pjp.getSignature().getName(), argTypes);
        } catch (NoSuchMethodException e) {
            logger.error("annotation no sucheMehtod", e);
        } catch (SecurityException e) {
            logger.error("annotation SecurityException", e);
        }
        return method;

    }
}　　

　调用类

@Service
@Transactional
public class UserServiceImpl extends BaseServiceImpl<User, Integer> implements UserService {

    @Autowired
    private UserDaoImpl userDaoImpl;

    @Override
    //key名字自定义  fieldKey可以看Spring EL表达式
    @Cacheable(key = "getUser",fieldKey = "#user.getUserName()")
    public User getUser(User user) {
        List<User> users = userDaoImpl.getUser(user);
        if (!users.isEmpty() && users.size() > 0) {
            user=users.get(0);
            return user;
        } else {
            return null;
        }
    }
}