SpringBoot高并发下控制限流的几种实现方法

import com.google.common.util.concurrent.RateLimiter;

@Service
public class MyService {

    private final RateLimiter rateLimiter = RateLimiter.create(10.0); // 每秒允许10个请求

    public void doSomething() {
        if (rateLimiter.tryAcquire()) {
            // 执行业务逻辑
        } else {
            // 请求被拒绝，可以返回错误信息或进行其他处理
        }
    }
}

// 自定义限流注解
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface RateLimit {
    double permitsPerSecond() default 1.0; // 每秒允许通过的请求数
}

// 使用AspectJ实现切面
@Aspect
@Component
public class RateLimitAspect {

    @Autowired
    private Map<String, RateLimiter> rateLimiterMap; // 假设这里有一个RateLimiter的Map，用于存储不同接口的RateLimiter

    @Around("@annotation(rateLimit)")
    public Object around(ProceedingJoinPoint joinPoint, RateLimit rateLimit) throws Throwable {
        String key = joinPoint.getSignature().toShortString(); // 根据方法签名生成key
        RateLimiter rateLimiter = rateLimiterMap.getOrDefault(key, RateLimiter.create(rateLimit.permitsPerSecond()));
        if (rateLimiter.tryAcquire()) {
            return joinPoint.proceed(); // 执行原方法
        } else {
            // 请求被拒绝，可以抛出异常或返回错误信息
            throw new RuntimeException("Too many requests, please try again later.");
        }
    }
}

import com.alibaba.csp.sentinel.annotation.SentinelResource;

@Service
public class MyService {

    @SentinelResource(value = "doSomething", blockHandler = "blockHandler")
    public void doSomething() {
        // 执行业务逻辑
    }

    public void blockHandler(BlockException ex) {
        // 处理被限流的请求
    }
}