Java 实现限流器处理Rest接口请求详解流程

        <dependency>
            <groupId>com.Google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>31.0.1-jre</version>
        </dependency>

package com.huyi.csdn.tools.rate;
 
import com.google.common.util.concurrent.Monitor;
import com.google.common.util.concurrent.RateLimiter;
 
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.function.Consumer;
 

public class RequestRateLimiter {
  // 请求队列
  private final ConcurrentLinkedQueue<Request> bucket = new ConcurrentLinkedQueue<>();
  // 队列上限
  private static final int BUCKET_CAPACITY = 100;
  // 漏桶下沿水流速度
  private final RateLimiter rateLimiter = RateLimiter.create(10.0D);
  // 请求监视器
  private final Monitor requestMoniter = new Monitor();
  // 处理监视器
  private final Monitor handleMoniter = new Monitor();
 
  
  public static class Request {
    private int data;
 
    public Request(int data) {
      this.data = data;
    }
 
    @Override
    public String toString() {
      return "Request{" + "data=" + data + '}';
    }
  }
 
  public void submitRequest(int data) {
    this.submitRequest(new Request(data));
  }
 
  public void submitRequest(Request request) {
    // 请求监视器，创建监视向导，队列数据量小于上限
    if (requestMoniter.enterIf(requestMoniter.newGuard(() -> bucket.size() < BUCKET_CAPACITY))) {
      try {
        boolean result = bucket.offer(request);
        if (result) {
          System.out.println("成功向队列加入新的请求！" + Thread.currentThread() + " request:" + request);
        } else {
          System.out.println("加入新请求失败！");
        }
      } finally {
        requestMoniter.leave();
      }
    } else {
      // 队列已满
      // System.out.println("请求队列已经上限，请稍后重试！");
    }
  }
 
  // 处理请求方法
  public void handleRequest(Consumer<Request> consumer) {
    if (handleMoniter.enterIf(handleMoniter.newGuard(() -> !bucket.isEmpty()))) {
      try {
        // 匀速处理
        rateLimiter.acquire();
        consumer.accept(bucket.poll());
      } finally {
        handleMoniter.leave();
      }
    }
  }
}

package com.huyi.csdn.tools.rate;
 
import java.time.LocalTime;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.stream.IntStream;
 

public class TestRateLimiter {
  private static final AtomicInteger DATA = new AtomicInteger(0);
  private static final RequestRateLimiter HANDLE = new RequestRateLimiter();
 
  public static void main(String[] args) {
    IntStream.range(0, 10)
        .forEach(
            (x) ->
                new Thread(
                        () -> {
                          while (true) {
                            HANDLE.submitRequest(DATA.getAndIncrement());
                            try {
                              TimeUnit.MILLISECONDS.sleep(100);
                            } catch (InterruptedException e) {
                              e.printStackTrace();
                            }
                          }
                        })
                    .start());
 
    IntStream.range(0, 20)
        .forEach(
            (x) ->
                new Thread(
                        () -> {
                          while (true) {
                            HANDLE.handleRequest(
                                y ->
                                    System.out.println(
                                        LocalTime.now() + ":处理数据 -> " + y.toString()));
                          }
                        })
                    .start());
  }
}