class Http2ConnectionHandler extends ByteToMessageDecoder implements Http2LifecycleManager,
                                                                            ChannelOutboundHandler {

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        if (getEmbeddedHttp2Exception(cause) != null) {
            // Some exception in the causality chain is an Http2Exception - handle it.
            onError(ctx, false, cause);
        } else {
            super.exceptionCaught(ctx, cause);
        }
    }

    protected  Http2ConnectionHandler(Http2ConnectionDecoder decoder, Http2ConnectionEncoder encoder,
                                     Http2Settings initialSettings);
      Http2ConnectionHandler(boolean server, Http2FrameWriter frameWriter, Http2FrameLogger frameLogger,
                    Http2Settings initialSettings);

}