NIO Selector activating immediately and not blocking on select(). Spinning through loop uncontrollably

I have a selector thread: http://www.copypastecode.com/83442/

It has a list of ChangeRequests it processes, then blocks, then processes Keys. The methods connect and send are the only ones sending wakeup() to the selector.

When I establish 2 Servers and run separate select loops, it happens that the 2nd server doesn't seem to block on select(). I say this because no log message get printed, either in connect or send, no in the processing of keys. When infinitely looping, no keys are being processed.

How can I fix this situation? If defeats the purpose of using non-blocking IO.

protected void startSelectorThread() {
    new Thread() {
        public void run() {
            log.debug("NIOThreadedConnection: Selector Thread started; " + serverSocketChannel);
            selectorRunning = true;
      开发者_如何学C      while (selectorRunning == true) {
                log.debug(".");
                processChangeRequests();
                blockForSelectorTraffic();
                processSelectionKeys();
            }
            System.out.println("Selector Thread terminated");
            nioServer.stoppedListening(null);
        }
    }.start();
}


protected void processChangeRequests() {
    synchronized (pendingChanges) {
        for(ChangeRequest change:pendingChanges) {
            switch (change.type) {
                case ChangeRequest.CHANGEOPS: {
                    SelectionKey key = change.socket.keyFor(socketSelector);
                    if (key == null) {
                        continue;
                    }
                    key.interestOps(change.ops);
                    continue;
                }
                // Client only:
                case ChangeRequest.REGISTER: {
                    try {
                        log.debug("future connection with channel: " + change.socket);
                        change.socket.register(socketSelector, change.ops);
                    } catch (ClosedChannelException e) {
                        log.debug("closed channel(" + change.socket + ")");
                    }
                    continue;
                }
            }
        }
        pendingChanges.clear();
    }
}


protected void blockForSelectorTraffic() {
    try {
        socketSelector.select();
    } catch (IOException e) {
        e.printStackTrace();
    }
}


protected void processSelectionKeys() {
    Iterator<SelectionKey> selectedKeys = socketSelector.selectedKeys().iterator();
    while (selectedKeys.hasNext()) {
        SelectionKey key = selectedKeys.next();
        log.debug("found a key: " + key);
        selectedKeys.remove();
        if (!key.isValid()) {
            log.debug("key invalid: " + key);
            continue;
        }
        try {
            if (key.isAcceptable()) {
                log.debug("accept with a ListenConnection: " + key);
                try {
                    accept(key);
                } catch (ClosedChannelException e) {
                    log.debug("closed server channel(" + key + ")");
                }
            } else if (key.isConnectable()) {
                log.debug("finishing connection: " + key);
                finishConnection(key);
            } else if (key.isReadable()) {
                log.debug("reading with key: " + key);
                int bytesRead = read(key);
                log.debug("read: " + bytesRead + " with key: " + key);
            } else if (key.isWritable()) {
                log.debug("writing with key: " + key);
                int bytesWritten = write(key);
                log.debug("write: " + bytesWritten + " with key: " + key);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    log.debug("all done with keys");
}

Thanks, Robert