1

所以，我有这个非常灵活的 Phaser，但似乎我错过了一些东西。
我已经成功使用了 CyclicBarrier，但现在我也想要更灵活的东西，就像我说的那样。所以这里是代码：

声明：

private static final CountDownLatch synchronizer = new CountDownLatch(1);
private static AtomicBoolean HAS_TIMED_OUT = new AtomicBoolean(false);


代码：

try {
    logger.INFO("CONNECTED - Peer ID properties: " + SYS_NEWLINE + peerSocket + SYS_NEWLINE + pID, true);

    final int peerKQueries = sp.getInteger(peerSocket);
    peerObjects = new String[peerKQueries];
    peerValues = new BigDecimal[peerKQueries];
    for ( int i = 0; i < peerObjects.length; i++ )
       peerObjects[i] = sp.getString(peerSocket);
    for ( int i = 0; i < peerValues.length; i++ )
       peerValues[i] = sp.getBigDecimal(peerSocket);

    final int phase1a = htPhaser1a.arrive();
    if ( phase1a < 0 ) {
        logger.ERROR("Rejecting Super Peer thread " + THREAD_ID + " because it arrived lately for Phase 1a!", true);
        sp.close(peerSocket);
        throw new IllegalThreadStateException();
    } else {
        logger.INFO(pID + " -> Arrived in HT phase 1a. Total arrivals: "+htPhaser1a.getArrivedParties(), true);
        logger.INFO("Super Peer thread " + THREAD_ID + " will advance to HT Phase 1b/2 (phase number is "+phase1a+").", true);
        // The last peer should also unblock the barrier.
        if ( htPhaser1a.getArrivedParties() == TOTAL_PEERS.get() ) {
          htPhaser1a.arrive();
          synchronizer.countDown();
        }
            htPhaser1a.awaitAdvanceInterruptibly(phase1a, 30, TimeUnit.SECONDS);
    }

} catch (IOException e) {
    logger.ERROR("Super Peer thread " + THREAD_ID + " encountered an I/O error.", true);
    sp.close(peerSocket);
    throw new IllegalThreadStateException();
} catch (TimeoutException e) {
    logger.INFO("Super Peer thread " + THREAD_ID + " timed out but will advance to HT Phase 1b/2.", true);
    if ( HAS_TIMED_OUT.compareAndSet(false, true) ) {
        logger.INFO("Parties NOT arrived in the timeout: "+(htPhaser1a.getUnarrivedParties()-1), true);
        resetCriticalData(htPhaser1a.getArrivedParties());
        htPhaser1a.forceTermination();
        instantiateHTPhase1b();
        instantiateHTPhase2();
        instantiateHTPatch();
        synchronizer.countDown();
    }
} finally {
    logger.INFO("Super Peer thread "+THREAD_ID+" is blocked!", true);
    synchronizer.await();
    logger.INFO("Super Peer thread's "+THREAD_ID+" blocking waived!", true);
}

sp.getSomething();是 I/O 调用。
考虑到此代码示例由多个线程运行。

这是我的问题：我已确保不会超过 MAX_CLIENTS 到达移相器，所以如果 MAX_CLIENTS 到达，一切都很好。但是，我遇到了 TimeoutException 的问题。第一个是客户端（比如线程 A）将能够到达阶段的时间窗口（又名竞争条件），然后线程 B 中发生 TimeoutException，我正在线程 B 中动态实例化另一个带有到达方数量的移相器（比如 5），但随后线程 A 已经到达阶段（又名 phase1a 未发现 < 0）。我该如何纠正？我正在考虑使用信号量，但我认为这不值得努力，因为那样我可能需要重新考虑我这样做的方式。我还考虑过使用 Timer 并增加一个AtomicInteger变量和当定时器到期时动态实例化Phaser。关于如何解决这个问题的任何想法？

编辑：
文档有一种bulkRegister(int parties)方法，但措辞有点奇怪：

将给定数量的新未到达方添加到此移相器。如果正在进行的 onAdvance(int, int) 调用正在进行中，则此方法可能会在返回之前等待其完成。如果此移相器有父移相器，并且给定的参与方数量大于零，并且此移相器之前没有注册参与方，则此子移相器也向其父移相器注册。如果此移相器终止，则注册尝试无效，并返回负值。

问题： “可能”这个词让我感到困惑！“可能”如可能或“可能”

编辑：
解决。在下面检查我的答案。

4

1 回答 1

1

声明：

private static final CountDownLatch PEER = new CountDownLatch(1);
private static AtomicBoolean HAS_TIMED_OUT = new AtomicBoolean(false);
htPeerPhaser = new Phaser();


代码：

...
htPeerPhaser.register(); // Called only once.
...
// Note: Server application has guaranteed that no more than the maximum number of peers will arrive.
try {
    logger.INFO("CONNECTED - Peer ID properties: " + SYS_NEWLINE + peerSocket + SYS_NEWLINE + pID, true);
    final int peerKQueries = sp.getInteger(peerSocket);
    peerObjects = new String[peerKQueries];
    peerValues = new BigDecimal[peerKQueries];
    for ( int i = 0; i < peerObjects.length; i++ )
        peerObjects[i] = sp.getString(peerSocket);
    for ( int i = 0; i < peerValues.length; i++ )
        peerValues[i] = sp.getBigDecimal(peerSocket);
    final int registrationID = htPeerPhaser.bulkRegister(1);
    if ( registrationID < 0 ) {
        logger.ERROR("Rejecting Super Peer thread " + THREAD_ID + " because peer registration has stopped!", true);
        sp.close(peerSocket);
        throw new IllegalThreadStateException();
    }
    logger.INFO(pID + " -> Registered for HT phase 1.", true);
    logger.INFO("Super Peer thread " + THREAD_ID + " will advance to HT Phase 1/2.", true);
    // The last peer should also unblock the barrier.
    if ( htPeerPhaser.getRegisteredParties() == TOTAL_PEERS.get()+1 ) {
        htPeerPhaser.forceTermination();
        PEER.countDown();
    }
    htPeerPhaser.awaitAdvanceInterruptibly(registrationID, 30, TimeUnit.SECONDS);

} catch (IOException e) {
    logger.ERROR("Super Peer thread " + THREAD_ID + " encountered an I/O error.", true);
    sp.close(peerSocket);
    throw new IllegalThreadStateException();
} catch (TimeoutException e) {
    htPeerPhaser.forceTermination();
    logger.INFO("Super Peer thread " + THREAD_ID + " timed out but will advance to HT Phase 1b/2.", true);
    if ( HAS_TIMED_OUT.compareAndSet(false, true) && htPeerPhaser.getRegisteredParties() < TOTAL_PEERS.get()+1 ) {
        final int arrivedPeers = htPeerPhaser.getRegisteredParties()-1;
        logger.INFO("Parties that arrived before timeout: "+arrivedPeers, true);
        final int unarrivedPeers = TOTAL_PEERS.get()-arrivedPeers;
        logger.INFO("Parties NOT arrived due to timeout: "+unarrivedPeers, true);
        resetCriticalData(arrivedPeers);
        instantiateHTPhase1b();
        instantiateHTPhase2();
        instantiateHTPatch();
        PEER.countDown();
        logger.INFO("Super Peer thread " + THREAD_ID + " re-instantiated critical data.", true);
    }
}
logger.INFO("Super Peer thread "+THREAD_ID+" is blocked!", true);
PEER.await();
logger.INFO("Super Peer thread's "+THREAD_ID+" blocking waived!", true);
于 2011-10-05T12:22:22.873 回答