Wie man Java Multithreading richtig macht ⇐ Java

[Anonymous]

Wie im folgenden Code -Snippet gezeigt, gibt es einen Bahnhof und zwei Züge. Station ist ein Faden, und Züge sind zwei verschiedene Fäden.

Code: Select all

    ThreadGroup group = new ThreadGroup("MyThreadGroup");
MainStation mainStation = new MainStation();
Thread stationThread= new Thread(group,mainStation);
TrainA trainA = new TrainA(mainStation);
TrainB trainB=new TrainB(mainStation);
Thread trainAThread=new Thread(group,trainA);
Thread trainBThread=new Thread(group,trainB);

stationThread.setDaemon(true);

ExecutorService executorService= Executors.newFixedThreadPool(3);
executorService.submit(stationThread);
executorService.submit(trainAThread);
executorService.submit(trainBThread);
executorService.shutdown();
< /code>
Aber wenn ich das Programm ausführe, führt nur ein Zug -Thread mit dem Bahnhofsthread aus und nicht mit beiden Zug -Threads. < /p>
Main stattion
Train a running
Train B running
TrainA Removing people from station value--0
TrainB Removing people from station value--0
Station adding people to queue value--0 size--1
TrainA Queue size after removing --0
TrainA Removing people from station value--1
Station adding people to queue value--1 size--0
TrainA Queue size after removing --0
Station adding people to queue value--2 size--1
TrainA Removing people from station value--2
TrainA Queue size after removing --0
Station adding people to queue value--3 size--1
TrainA Removing people from station value--3
TrainA Queue size after removing --0
Station adding people to queue value--4 size--1
TrainA Removing people from station value--4
TrainA Queue size after removing --0
Station adding people to queue value--5 size--1
TrainA Removing people from station value--5
TrainA Queue size after removing --0
Station adding people to queue value--6 size--1
TrainA Removing people from station value--6
TrainA Queue size after removing --0
Station adding people to queue value--7 size--1
TrainA Removing people from station value--7
TrainA Queue size after removing --0
Station adding people to queue value--8 size--1
TrainA Removing people from station value--8
TrainA Queue size after removing --0
Station adding people to queue value--9 size--1
TrainA Removing people from station value--9
TrainA Queue size after removing --0
< /code>
Wenn Sie beobachten, dass der obige Protokoll nur Menschen vom Bahnhof entfernt und nicht den Zug b.public class MainStation implements Runnable{

private volatile ConcurrentLinkedDeque queue=new ConcurrentLinkedDeque();
private final static People people=new People(10);

@Override
public void run() {
synchronized(this){
for (int i = 0; i < people.getCount(); i++) {
//System.out.println("Station adding people to queue "+i);
this.queue.add(i);
System.out.println("Station adding people to queue value--" + i + " size--" + this.queue.size());
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
}

}

public ConcurrentLinkedDeque getQueue() {
return queue;
}
< /code>
} < /p>
Züge A und B < /p>
public class TrainA  implements Runnable{

private MainStation station=null;

public TrainA(MainStation station){
this.station=station;
}

@Override
public void run() {
System.out.println("Train a running");
while (true) {
for (int i = 0; i < station.getQueue().size(); i++) {
System.out.println("TrainA Removing people from station value--" + station.getQueue().getFirst());
if(station!=null&&station.getQueue()!=null)station.getQueue().removeFirst();
System.out.println("TrainA Queue size after removing --" + station.getQueue().size());
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
throw new RuntimeException(e);
}
}
}

}

}