Java多线程 用join方法控制线程按顺序执行。

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java多线程CountDownLatch简单测试

测试代码如下：

public class ThreadsTest {


    public static void main(String[] args) throws WriteException, IOException {

        List list = new ArrayList<>();
        // 模拟20个客户端访问
        for (int i=0;i<10;i++) {
            Runnable run = new Runnable() {
                @Override
                public void run() {
                    try {
                        for(int j=0; j<6;j++){
                            Thread.sleep(100);
                            System.out.println("--------j----threadName-----" + j + "====" + Thread.currentThread().getName());
                        }
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            };
            list.add(run);
        }
        System.out.println("------------都结束了?????????------------");
        for(int j=0;j 
 
 
实际输出如下：
 
------------都结束了?????????------------
 --------j----threadName-----0====Thread-0
 --------j----threadName-----1====Thread-0
 --------j----threadName-----2====Thread-0
 --------j----threadName-----3====Thread-0
 --------j----threadName-----4====Thread-0
 --------j----threadName-----5====Thread-0
 --------j----threadName-----0====Thread-1
 --------j----threadName-----1====Thread-1
 --------j----threadName-----2====Thread-1
 --------j----threadName-----3====Thread-1
 --------j----threadName-----4====Thread-1
 --------j----threadName-----5====Thread-1
 --------j----threadName-----0====Thread-2
 --------j----threadName-----1====Thread-2
 --------j----threadName-----2====Thread-2
 --------j----threadName-----3====Thread-2
 --------j----threadName-----4====Thread-2
 --------j----threadName-----5====Thread-2
 --------j----threadName-----0====Thread-3
 --------j----threadName-----1====Thread-3
 --------j----threadName-----2====Thread-3
 --------j----threadName-----3====Thread-3
 --------j----threadName-----4====Thread-3
 --------j----threadName-----5====Thread-3
 --------j----threadName-----0====Thread-4
 --------j----threadName-----1====Thread-4
 --------j----threadName-----2====Thread-4
 --------j----threadName-----3====Thread-4
 --------j----threadName-----4====Thread-4
 --------j----threadName-----5====Thread-4
 --------j----threadName-----0====Thread-5
 --------j----threadName-----1====Thread-5
 --------j----threadName-----2====Thread-5
 --------j----threadName-----3====Thread-5
 --------j----threadName-----4====Thread-5
 --------j----threadName-----5====Thread-5
 --------j----threadName-----0====Thread-6
 --------j----threadName-----1====Thread-6
 --------j----threadName-----2====Thread-6
 --------j----threadName-----3====Thread-6
 --------j----threadName-----4====Thread-6
 --------j----threadName-----5====Thread-6
 --------j----threadName-----0====Thread-7
 --------j----threadName-----1====Thread-7
 --------j----threadName-----2====Thread-7
 --------j----threadName-----3====Thread-7
 --------j----threadName-----4====Thread-7
 --------j----threadName-----5====Thread-7
 --------j----threadName-----0====Thread-8
 --------j----threadName-----1====Thread-8
 --------j----threadName-----2====Thread-8
 --------j----threadName-----3====Thread-8
 --------j----threadName-----4====Thread-8
 --------j----threadName-----5====Thread-8
 --------j----threadName-----0====Thread-9
 --------j----threadName-----1====Thread-9
 --------j----threadName-----2====Thread-9
 --------j----threadName-----3====Thread-9
 --------j----threadName-----4====Thread-9
 --------j----threadName-----5====Thread-9
 都结束了