Spring Boot使用RateLimiter通过AOP方式进行限流

1、引入依赖

     com.google.guava
     guava
     25.1-jre

2、自定义注解

@Target({ElementType.PARAMETER, ElementType.METHOD})    
@Retention(RetentionPolicy.RUNTIME)    
@Documented    
public  @interface ServiceLimit { 
     String description()  default "";
}

3、AOP实现类

@Component
@Scope
@Aspect
public class LimitAspect {
    ////每秒只发出5个令牌，此处是单进程服务的限流,内部采用令牌捅算法实现
    private static   RateLimiter rateLimiter = RateLimiter.create(5.0);
    
    //Service层切点  限流
    @Pointcut("@annotation(com.itstyle.seckill.common.aop.ServiceLimit)")  
    public void ServiceAspect() {
        
    }
    
    @Around("ServiceAspect()")
    public  Object around(ProceedingJoinPoint joinPoint) { 
        Boolean flag = rateLimiter.tryAcquire();
        Object obj = null;
        try {
            if(flag){
                obj = joinPoint.proceed();
            }
        } catch (Throwable e) {
            e.printStackTrace();
        } 
        return obj;
    } 
}

4、使用

        @Override
    @ServiceLimit
    @Transactional
    public Result startSeckil(long seckillId,long userId) {
        //todo 操作
    }