面对线程

Question

我怀疑我在循环中创建了几个线程，它将调用我已经实现的run方法。我怀疑虽然我已经编写了t.join而未完成其run方法，但主线程正在向前推进并执行后续步骤。怎么阻止这个？

for(int j=1;j<=iteration;j++){
    Thread t=null;
    System.out.println("Starting Iteration-"+j);
    for(int i=1;i<=totalNumberOfUsers;i++) {
        t=new Thread(new CasLoadTest());
        t.setName("User"+i);
        t.start();
        Thread.sleep((long) (delayPeriod*1000));
    }
    t.join();
    for(Map.Entry<String,Long> map:latencyMap.entrySet()){
        System.out.println(map.getKey()+"-"+map.getValue());
    }
    System.out.println("Iteration"+j+"-->Max:"+Collections.max(latencyMap.values()));
    System.out.println("Iteration"+j+"-->Min:"+Collections.min(latencyMap.values()));
    double temp=(double)(lastUserLoggedIn-firstUserLoggedIn)/1000;
    System.out.println("Iteration"+j+"-->Total Number of Users Logged In (Users\\Sec)--"+totalNumberOfUsers/temp);

    latencyMap.clear();
    threadCount = totalNumberOfUsers;
    count = 0;
    Thread.sleep(30000);
}

Answer 1

收集您在列表中创建的所有主题。然后你可以在继续使用main方法之前等待所有人退出他们的操作。

ArrayList<Thread> allThreads = new ArrayList<>(); // create a list of all Threads
for(int i=1;i<=totalNumberOfUsers;i++) {
    t=new Thread(new CasLoadTest());
    allThreads.add(t); // add new Thread to list
    ...
}
...
// wait for all Threads to end before executing next code
for(Thread thread : allThreads)
    thread.join();