@Override
public void apply(final Task task) {
    if (this.shutdownLatch != null) {
        Utils.runClosureInThread(task.getDone(), new Status(RaftError.ENODESHUTDOWN, "Node is shutting down."));
        throw new IllegalStateException("Node is shutting down");
    }
    Requires.requireNonNull(task, "Null task");

    // 创建一个 LogEntry 对象用于承载日志数据
    final LogEntry entry = new LogEntry();
    entry.setData(task.getData());
    int retryTimes = 0;
    try {
        final EventTranslator<LogEntryAndClosure> translator = (event, sequence) -> {
            event.reset();
            event.done = task.getDone();
            event.entry = entry;
            event.expectedTerm = task.getExpectedTerm();
        };
        while (true) {
          // 异步化发送日志
            if (this.applyQueue.tryPublishEvent(translator)) {
                break;
            } else {
                retryTimes++;
                if (retryTimes > MAX_APPLY_RETRY_TIMES) {
                    Utils.runClosureInThread(task.getDone(), new Status(RaftError.EBUSY, "Node is busy, has too many tasks."));
                    LOG.warn("Node {} applyQueue is overload.", getNodeId());
                    this.metrics.recordTimes("apply-task-overload-times", 1);
                    return;
                }
                ThreadHelper.onSpinWait();
            }
        }

    } catch (final Exception e) {
        Utils.runClosureInThread(task.getDone(), new Status(RaftError.EPERM, "Node is down."));
    }
}