Question

我在Android的asmack库中遇到了一个奇怪的问题。该库使用ExecutorService来解析传入的数据包，如：

private ExecutorService listenerExecutor;

listenerExecutor = Executors.newSingleThreadExecutor(new ThreadFactory() {

        public Thread newThread(Runnable runnable) {
            Thread thread = new Thread(runnable,
                    "Smack Listener Processor (" + connection.connectionCounterValue + ")");
            thread.setDaemon(true);
            return thread;
        }
    });

(...)

listenerExecutor.submit(new ListenerNotification(packet));

(...)

/**
 * A runnable to notify all listeners of a packet.
 */
private class ListenerNotification implements Runnable {

    private Packet packet;

    public ListenerNotification(Packet packet) {
        this.packet = packet;
    }

    public void run() {
        for (ListenerWrapper listenerWrapper : connection.recvListeners.values()) {
            listenerWrapper.notifyListener(packet);
        }
    }
}

一切正常，直到调用submit（）方法，调用ListenerNotification的构造函数，但不再调用ListenerNotification中的run（）方法。

这可能是什么原因？ ExecutorService中是否有一些机制可能会导致调用提交被忽略？

Answer 1

正如所预料的那样，错误就在我身边。

我在代码中实现了一个Roster Packet侦听器并覆盖了processPacket方法：

@Override
public void processPacket(Packet packet) {
    if (packet instanceof RosterPacket) {
        RosterPacket rosterPacket = (RosterPacket) packet;
        Logger.d(LOGTAG, "Initial roster packet received: " + rosterPacket.getRosterItemCount());
        mConnection.removePacketListener(this);
        fireOnInitialRosterPacketReceived(rosterPacket);
    }
}

但是，我的内部监听器调用方法引入了一个无限循环：

private void fireOnInitialRosterPacketReceived(RosterPacket rosterPacket) {
    Iterator<SessionListener> it = mSessionListeners.iterator();
    while (it.hasNext()) {
        // it.next().onInitialRosterPacketReceived(mConnection,
        // rosterPacket);
    }
}

这阻止了执行程序启动的线程，以便后续的提交调用不会再次触发该线程。

ExecutorService不会在Runnable中调用run（）

1 个答案: