EchoHandler Class — netty Architecture

Source Code

codec-http/src/test/java/io/netty/handler/codec/spdy/SpdySessionHandlerTest.java lines 324–391

    private static class EchoHandler extends ChannelInboundHandlerAdapter {
        private final int closeSignal;
        private final boolean server;

        EchoHandler(int closeSignal, boolean server) {
            this.closeSignal = closeSignal;
            this.server = server;
        }

        @Override
        public void channelActive(ChannelHandlerContext ctx) throws Exception {
            // Initiate 4 new streams
            int streamId = server ? 2 : 1;
            SpdySynStreamFrame spdySynStreamFrame =
                    new DefaultSpdySynStreamFrame(streamId, 0, (byte) 0);
            spdySynStreamFrame.setLast(true);
            ctx.writeAndFlush(spdySynStreamFrame);
            spdySynStreamFrame.setStreamId(spdySynStreamFrame.streamId() + 2);
            ctx.writeAndFlush(spdySynStreamFrame);
            spdySynStreamFrame.setStreamId(spdySynStreamFrame.streamId() + 2);
            ctx.writeAndFlush(spdySynStreamFrame);
            spdySynStreamFrame.setStreamId(spdySynStreamFrame.streamId() + 2);
            ctx.writeAndFlush(spdySynStreamFrame);

            // Limit the number of concurrent streams to 1
            SpdySettingsFrame spdySettingsFrame = new DefaultSpdySettingsFrame();
            spdySettingsFrame.setValue(SpdySettingsFrame.SETTINGS_MAX_CONCURRENT_STREAMS, 1);
            ctx.writeAndFlush(spdySettingsFrame);
        }

        @Override
        public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
            if (msg instanceof SpdySynStreamFrame) {

                SpdySynStreamFrame spdySynStreamFrame = (SpdySynStreamFrame) msg;
                if (!spdySynStreamFrame.isUnidirectional()) {
                    int streamId = spdySynStreamFrame.streamId();
                    SpdySynReplyFrame spdySynReplyFrame = new DefaultSpdySynReplyFrame(streamId);
                    spdySynReplyFrame.setLast(spdySynStreamFrame.isLast());
                    for (Map.Entry<CharSequence, CharSequence> entry: spdySynStreamFrame.headers()) {
                        spdySynReplyFrame.headers().add(entry.getKey(), entry.getValue());
                    }

                    ctx.writeAndFlush(spdySynReplyFrame);
                }
                return;
            }

            if (msg instanceof SpdySynReplyFrame) {
                return;
            }

            if (msg instanceof SpdyDataFrame ||
                msg instanceof SpdyPingFrame ||
                msg instanceof SpdyHeadersFrame) {

                ctx.writeAndFlush(msg);
                return;
            }

            if (msg instanceof SpdySettingsFrame) {
                SpdySettingsFrame spdySettingsFrame = (SpdySettingsFrame) msg;
                if (spdySettingsFrame.isSet(closeSignal)) {
                    ctx.close();
                }
            }
        }
    }