1、建立多執行緒和執行緒池的程式碼：

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;
 
int threadSize = 100;  //開啟的執行緒數
//建立執行緒池
ExecutorService executorService = Executors.newFixedThreadPool(threadSize);
long start = System.currentTimeMillis();
//讓執行緒池中的每一個執行緒都開始工作
 

for (int j = 0; j < threadSize; j++) {
    //執行執行緒
    executorService.execute(new TestPerformance(threadSize));
}
//等執行緒全部執行完後關閉執行緒池
executorService.shutdown();
executorService.awaitTermination(Integer.MAX_VALUE, TimeUnit.DAYS);
long end = System.currentTimeMillis();
System.out.println("測試次數：" + TestPerformance.atomicInteger.get());
System.out.println(
 
"用時：" + (end - start));
System.out.println("速度：" + TestPerformance.atomicInteger.get() * 1000 / (end - start) + "次/秒");

2、具體要測試效能的程式碼：

package com.test.performance;
 
 
import java.util.concurrent.atomic.AtomicInteger;
 
/**
 * 測試效能.
 */
public class TestPerformance implements Runnable {
 
    //每個執行緒的執行次數
 

    private int size;
 
    //記錄多執行緒的總執行次數，保證高併發下的原子性
    public static AtomicInteger atomicInteger = new AtomicInteger(0);
 
    public TestPerformance(int size) {
        this.size = size;
    }
 
    @Override
    public void run() {
 
        int count = 0;
        while (count < size) {
            count++;
 
            atomicInteger.getAndIncrement();
 
            ///
        //在此寫入需要測試效能的程式碼塊
        ///
 
            System.out.println("執行緒ID與對應的執行次數：" + Thread.currentThread().getId() + "--->" + count);
        }
    }
}

轉：https://blog.csdn.net/weixin_43192102/article/details/106195948