@Override
    public boolean sinkFinish() {
        boolean finished = false;
        packageAckInfoLock.writeLock().lock();
        if (ackInfoList.isEmpty()) {
            finished = true;
        }
        packageAckInfoLock.writeLock().unlock();
        return finished;
    }
check whether all stream id messages finished
inlong-agent/agent-plugins/src/main/java/org/apache/inlong/agent/plugin/sinks/ProxySink.java