基于netty實現(xiàn)Webscoket相對來說就是相當簡單趾诗，所以本講中就不搞太復(fù)雜的了，給大家看一個類圖礁遣，和一段給pipeline添加handler郎逃，就可以完全了解hivemq如何處理的了，其實跟幾乎所有需要使用netty去支持websocket的處理一致豁护。
websocket
public class WebsocketTransportChannelInitializer {
public static final int MAX_CONTENT_LENGTH = 65536;
private final WebsocketListener listener;
public WebsocketTransportChannelInitializer(WebsocketListener listener) {
this.listener = listener;
}
public void initChannel(Channel channel) {
//添加http協(xié)議編碼/解碼
channel.pipeline().addBefore(Pipelines.ALL_CHANNEL_GROUP_HANDLER, Pipelines.HTTP_SERVER_CODEC, new HttpServerCodec());
//添加HttpRequest消息聚合器
channel.pipeline().addAfter(Pipelines.HTTP_SERVER_CODEC, Pipelines.HTTP_OBJECT_AGGREGATOR, new HttpObjectAggregator(MAX_CONTENT_LENGTH));
//添加WebSocketServerProtocolHandler
String path = this.listener.getPath();
String subProtocols = getSubProtocols();
boolean allowExtensions = this.listener.getAllowExtensions();
channel.pipeline().addAfter(Pipelines.HTTP_OBJECT_AGGREGATOR, Pipelines.WEBSOCKET_SERVER_PROTOCOL_HANDLER, new WebSocketServerProtocolHandler(path, subProtocols, allowExtensions, Integer.MAX_VALUE));
//添加Websocket字節(jié)碼Handler
channel.pipeline().addAfter(Pipelines.WEBSOCKET_SERVER_PROTOCOL_HANDLER, Pipelines.WEBSOCKET_BINARY_FRAME_HANDLER, new WebsocketBinaryFrameHandler());
//添加websocket幀類型handler
channel.pipeline().addAfter(Pipelines.WEBSOCKET_BINARY_FRAME_HANDLER, Pipelines.WEBSOCKET_CONTINUATION_FRAME_HANDLER, new WebsocketContinuationFrameHandler());
//添加websocket文本handler
channel.pipeline().addAfter(Pipelines.WEBSOCKET_BINARY_FRAME_HANDLER, Pipelines.WEBSOCKET_TEXT_FRAME_HANDLER, new WebsocketTextFrameHandler());
//添加mqtt message轉(zhuǎn)換成websocket
channel.pipeline().addAfter(Pipelines.WEBSOCKET_TEXT_FRAME_HANDLER, Pipelines.MQTT_WEBSOCKET_ENCODER, new MqttWebsocketEncoder());
}
@VisibleForTesting
String getSubProtocols() {
return Joiner.on(",").join(this.listener.getSubprotocols());
}
}
