ChannelFuture() — netty Function Reference

Source Code

codec-http2/src/main/java/io/netty/handler/codec/http2/CompressorHttp2ConnectionEncoder.java lines 176–231

    @Override
    public ChannelFuture writeData(final ChannelHandlerContext ctx, final int streamId, ByteBuf data, int padding,
            final boolean endOfStream, ChannelPromise promise) {
        final Http2Stream stream = connection().stream(streamId);
        final EmbeddedChannel channel = stream == null ? null : (EmbeddedChannel) stream.getProperty(propertyKey);
        if (channel == null) {
            // The compressor may be null if no compatible encoding type was found in this stream's headers
            return super.writeData(ctx, streamId, data, padding, endOfStream, promise);
        }

        try {
            // The channel will release the buffer after being written
            channel.writeOutbound(data);
            ByteBuf buf = nextReadableBuf(channel);
            if (buf == null) {
                if (endOfStream) {
                    if (channel.finish()) {
                        buf = nextReadableBuf(channel);
                    }
                    return super.writeData(ctx, streamId, buf == null ? Unpooled.EMPTY_BUFFER : buf, padding,
                            true, promise);
                }
                // END_STREAM is not set and the assumption is data is still forthcoming.
                promise.setSuccess();
                return promise;
            }

            PromiseCombiner combiner = new PromiseCombiner(ctx.executor());
            for (;;) {
                ByteBuf nextBuf = nextReadableBuf(channel);
                boolean compressedEndOfStream = nextBuf == null && endOfStream;
                if (compressedEndOfStream && channel.finish()) {
                    nextBuf = nextReadableBuf(channel);
                    compressedEndOfStream = nextBuf == null;
                }

                ChannelPromise bufPromise = ctx.newPromise();
                combiner.add(bufPromise);
                super.writeData(ctx, streamId, buf, padding, compressedEndOfStream, bufPromise);
                if (nextBuf == null) {
                    break;
                }

                padding = 0; // Padding is only communicated once on the first iteration
                buf = nextBuf;
            }
            combiner.finish(promise);
        } catch (Throwable cause) {
            promise.tryFailure(cause);
        } finally {
            if (endOfStream) {
                cleanup(stream, channel);
            }
        }
        return promise;
    }