code: @Override
      public void channelHandlerContext(ChannelHandlerContext ctx) throws Http2Exception {
          this.ctx = checkNotNull(ctx, "ctx");
  
          // Writing the pending bytes will not check writability change and instead a writability change notification
          // to be provided by an explicit call.
          channelWritabilityChanged();
  
          // Don't worry about cleaning up queued frames here if ctx is null. It is expected that all streams will be
          // closed and the queue cleanup will occur when the stream state transitions occur.
  
          // If any frames have been queued up, we should send them now that we have a channel context.
          if (isChannelWritable()) {
              writePendingBytes();
          }
      }
docs: {@inheritDoc}
  <p>
  Any queued {@link FlowControlled} objects will be sent.