public void shutdown() {
   bossPool.shutdown();
   workerPool.shutdown();
   if (releasePools) {
     releasePools();
   }
 }
 public void releaseExternalResources() {
   bossPool.shutdown();
   workerPool.shutdown();
   releasePools();
 }
 public ServerSocketChannel newChannel(ChannelPipeline pipeline) {
   return new NioServerSocketChannel(this, pipeline, sink, bossPool.nextBoss(), workerPool);
 }