高并发解决方案限流技术-----漏桶算法限流

package com.aiyuesheng.utils;

import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;

import lombok.Getter;
import lombok.Setter;

/**
 * 
 * @author caich5 可以把水滴看成请求
 */
@Setter
@Getter
public class LeakyBucket {
    // 桶的容量
    private int capacity = 100;
    // 木桶剩余的水滴的量(初始化的时候的空的桶)
    private AtomicInteger water = new AtomicInteger(0);
    // 水滴的流出的速率 每1000毫秒流出1滴
    private int leakRate;
    // 第一次请求之后,木桶在这个时间点开始漏水
    private long leakTimeStamp;

    public LeakyBucket(int leakRate) {
        this.leakRate = leakRate;
    }

    public boolean acquire() {
        // 如果是空桶，就当前时间作为桶开是漏出的时间
        if (water.get() == 0) {
            leakTimeStamp = System.currentTimeMillis();
            water.addAndGet(1);
            return capacity == 0 ? false : true;
        }
        // 先执行漏水，计算剩余水量
        int waterLeft = water.get() - ((int) ((System.currentTimeMillis() - leakTimeStamp) / 1000)) * leakRate;
        water.set(Math.max(0, waterLeft));
        // 重新更新leakTimeStamp
        leakTimeStamp = System.currentTimeMillis();
        // 尝试加水,并且水还未满
        if ((water.get()) < capacity) {
            water.addAndGet(1);
            return true;
        } else {
            // 水满，拒绝加水
            return false;
        }
    }
}

package com.aiyuesheng.controller;

import java.util.concurrent.TimeUnit;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.aiyuesheng.hystrix.OrderHystrixCommand;
import com.aiyuesheng.service.OrderService;
import com.aiyuesheng.utils.LeakyBucket;
import com.aiyuesheng.utils.LimitService;
import com.alibaba.fastjson.JSONObject;
import com.google.common.util.concurrent.RateLimiter;

@RestController
public class Index {
//漏桶：水滴的漏出速率是每秒 1 滴
    private LeakyBucket leakyBucket = new LeakyBucket(1);

    @Autowired
    private OrderService orderService;
//漏桶限流
    @RequestMapping("/searchCustomerInfoByLeakyBucket")
    public Object searchCustomerInfoByLeakyBucket() {
        // 1.限流判断
        boolean acquire = leakyBucket.acquire();
        if (!acquire) {
            System.out.println("稍后再试！");
            return "稍后再试！";
        }
        // 2.如果没有达到限流的要求,直接调用接口查询
        System.out.println(orderService.searchCustomerInfo());
        return orderService.searchCustomerInfo();
    }
    

}