第七周作业

import lombok.Getter;
import lombok.Setter;
@Getter
@Setter
public class PerformanceSummary {
    /**
     * 平均响应时间
     */
    private Double avgRT;
    /**
     * 95%响应时间
     */
    private long percent95RT;
}

import org.apache.http.HttpEntity;
import org.apache.http.client.methods.CloseableHttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.atomic.AtomicInteger;
public class PerformanceLoadTest {
    public static void main(String[] args) {
        PerformanceSummary performanceSummary = performanceTest("http://wwww.baidu.com", 100, 10);
        System.out.println("平均响应时间："+performanceSummary.getAvgRT() + "ms,95%响应时间："+performanceSummary.getPercent95RT()+"ms");
    }
    public static PerformanceSummary performanceTest(String url, int totalNum, int concurrency) {
        CountDownLatch countDownLatch = new CountDownLatch(concurrency);
        AtomicInteger atomicInteger = new AtomicInteger(totalNum);
        List<Long> requestList = Collections.synchronizedList(new ArrayList<>(totalNum));
        for (int i = 0; i < concurrency; i++) {
            new Thread(() -> {
                while (true) {
                    if(atomicInteger.decrementAndGet() >= 0){
                        requestList.add(httpRequest(url));
                        try {
                            Thread.sleep(100);
                        } catch (InterruptedException e) {
                            e.printStackTrace();
                        }
                    } else {
                        break;
                    }
                }
                countDownLatch.countDown();
            }).start();
        }
        try {
            countDownLatch.await();
            PerformanceSummary summary = new PerformanceSummary();
            summary.setAvgRT(requestList.stream().mapToLong(Long::longValue).sum() * 1.0 / totalNum);
            requestList.sort(Comparator.comparing(Long::longValue));
            summary.setPercent95RT(requestList.get((int) (totalNum*0.95-1)));
            return summary;
        } catch (InterruptedException e) {
            e.printStackTrace();
            return null;
        }
    }
    public static long httpRequest(String url) {
        long t1 = System.currentTimeMillis();
        String result = get(url);
        long t2 = System.currentTimeMillis();
        return t2 - t1;
    }
    private static String get(String url) {
        HttpGet httpGet = new HttpGet(url);
        try(CloseableHttpClient httpClient = HttpClients.createDefault();
            CloseableHttpResponse httpResponse = httpClient.execute(httpGet);){
            HttpEntity entity = httpResponse.getEntity();
            String result = EntityUtils.toString(entity);
            return result;
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }
}