userEventTriggered() — netty Function Reference

Source Code

codec-http2/src/main/java/io/netty/handler/codec/http2/Http2FrameCodec.java lines 254–292

    @Override
    public final void userEventTriggered(final ChannelHandlerContext ctx, final Object evt) throws Exception {
        if (evt == Http2ConnectionPrefaceAndSettingsFrameWrittenEvent.INSTANCE) {
            // The user event implies that we are on the client.
            tryExpandConnectionFlowControlWindow(connection());

            // We schedule this on the EventExecutor to allow to have any extra handlers added to the pipeline
            // before we pass the event to the next handler. This is needed as the event may be called from within
            // handlerAdded(...) which will be run before other handlers will be added to the pipeline.
            ctx.executor().execute(new Runnable() {
                @Override
                public void run() {
                    ctx.fireUserEventTriggered(evt);
                }
            });
        } else if (evt instanceof UpgradeEvent) {
            UpgradeEvent upgrade = (UpgradeEvent) evt;
            try {
                onUpgradeEvent(ctx, upgrade.retain());
                Http2Stream stream = connection().stream(HTTP_UPGRADE_STREAM_ID);
                if (stream.getProperty(streamKey) == null) {
                    // TODO: improve handler/stream lifecycle so that stream isn't active before handler added.
                    // The stream was already made active, but ctx may have been null so it wasn't initialized.
                    // https://github.com/netty/netty/issues/4942
                    onStreamActive0(stream);
                }
                upgrade.upgradeRequest().headers().setInt(
                        HttpConversionUtil.ExtensionHeaderNames.STREAM_ID.text(), HTTP_UPGRADE_STREAM_ID);
                stream.setProperty(upgradeKey, true);
                InboundHttpToHttp2Adapter.handle(
                        ctx, connection(), decoder().frameListener(), upgrade.upgradeRequest().retain());
            } finally {
                upgrade.release();
            }
        } else {
            onUserEventTriggered(ctx, evt);
            ctx.fireUserEventTriggered(evt);
        }
    }