[开发测试]【JAVA单元测试】模拟高并发操作

近期有需求需要在项目中模拟高并发，研究了下网上博友的方案，写了这篇较为详细的实施方案，供以后参考。【源码在文末，即取即用】

1.定义高并发请求数与倒计时器

新建测试类HighConcurrentTest.java, 定义变量：

	// 并发请求数
    private static final int threadNum =10;
    // 倒计时器
    private CountDownLatch cdl =new CountDownLatch(threadNum);

2.设计实现Runable接口的用户请求类（在HighConcurrentTest类内定义）

	public class UserRequest implements Runnable {

        public UserRequest() {
        }

        public UserRequest(int no) {
            this.no = no;
        }

        public int no;

        // 重写run方法用于处理业务逻辑
        @Override
        public void run() {
            try {
                cdl.await();
            }catch (Exception e) {
                e.printStackTrace();
            }

            // todo 业务逻辑...
            System.out.println("now no = " + no);
        }
    }

3.测试高并发

	@Test
    public void testConcurrent(){
        System.out.println("start ... ");
        for (int i =0; i< threadNum; i++) {
            new Thread(new UserRequest(i)).start();
            // 倒计时计数
            cdl.countDown();
        }


        try {
            Thread.sleep(5000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("end ... ");
    }

执行后可发现日志顺序为：

start ... 
now no = 1
now no = 0
now no = 2
now no = 4
now no = 3
now no = 5
now no = 6
now no = 7
now no = 8
now no = 9
end ... 

说明线程间互不影响，模拟成功。

完整代码：

package xyz.dongzhensong.junitlearn.util;

import org.junit.Test;

import java.util.concurrent.CountDownLatch;

public class HighConcurrentTest {

    // 并发请求数
    private static final int threadNum =10;
    // 倒计时器
    private CountDownLatch cdl =new CountDownLatch(threadNum);

    public class UserRequest implements Runnable {

        public UserRequest() {
        }

        public UserRequest(int no) {
            this.no = no;
        }

        public int no;

        // 重写run方法用于处理业务逻辑
        @Override
        public void run() {
            try {
                cdl.await();
            }catch (Exception e) {
                e.printStackTrace();
            }

            // todo 业务逻辑...
            System.out.println("now no = " + no);
        }
    }

    @Test
    public void testConcurrent(){
        System.out.println("start ... ");
        for (int i =0; i< threadNum; i++) {
            new Thread(new UserRequest(i)).start();
            // 倒计时计数
            cdl.countDown();
        }


        try {
            Thread.sleep(5000);
            // 如线程内操作执行脚本，可先阻塞线程，等待子线程执行完成
//            Thread.currentThread().join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("end ... ");
    }
}