/** * Configure the pipeline for a cleartext upgrade from HTTP to HTTP/2. */ private void configureClearText(SocketChannel ch) { HttpClientCodec sourceCodec = new HttpClientCodec(); Http2ClientUpgradeCodec upgradeCodec = new Http2ClientUpgradeCodec(connectionHandler); HttpClientUpgradeHandler upgradeHandler = new HttpClientUpgradeHandler(sourceCodec, upgradeCodec, maxContentLength); ch.pipeline().addLast(sourceCodec, upgradeHandler, new UpgradeRequestHandler(), new UserEventLogger()); }