io.netty.channel.ChannelPipeline#context ( )源码实例Demo

@Override
protected void removeDecoder(ChannelHandlerContext ctx) throws Exception {
    ChannelPipeline p = ctx.pipeline();
    if (p.context(decoderName) != null) {
        p.remove(decoderName);
    }
}
 

private String getHttpDecoderContextName(ChannelPipeline pipeline){
    ChannelHandlerContext ctx = pipeline.context(HttpRequestDecoder.class);
    if (ctx == null) {
        ctx = pipeline.context(HttpServerCodec.class);
    }
    return ctx == null? null : ctx.name();
}
 

/**
 * Get the context for a the channel handler before a certain name.
 *
 * @param name     The name of the channel handler
 * @param pipeline The pipeline to target
 * @return The ChannelHandler before the one requested.
 */
public static ChannelHandlerContext getContextBefore(String name, ChannelPipeline pipeline) {
    boolean mark = false;
    for (String s : pipeline.names()) {
        if (mark) {
            return pipeline.context(pipeline.get(s));
        }
        if (s.equalsIgnoreCase(name))
            mark = true;
    }
    return null;
}
 

public static ChannelHandlerContext getPreviousContext(String name, ChannelPipeline pipeline) {
    String previous = null;
    for (String entry : pipeline.toMap().keySet()) {
        if (entry.equals(name)) {
            return pipeline.context(previous);
        }
        previous = entry;
    }
    return null;
}
 

@SuppressWarnings("deprecation")
private void remove(ChannelHandlerContext ctx) {
	try {
		ctx.channel().attr(OneTime.channelConfig).remove();
		ChannelPipeline pipeline = ctx.pipeline();
		if (pipeline.context(this) != null) {
			pipeline.remove(this);
		}
	} finally {
		negotiateMap.remove(ctx);
	}
}
 

@Override
public void channelRegistered(ChannelHandlerContext channelHandlerContext) throws Exception {
	try {
		initChannel(channelHandlerContext.channel());
	} catch (Throwable t) {
		exceptionCaught(channelHandlerContext, t);
	} finally {
		ChannelPipeline pipeline = channelHandlerContext.pipeline();
		if (pipeline.context(this) != null) {
			pipeline.remove(this);
		}
	}
	channelHandlerContext.pipeline().fireChannelRegistered();
}
 

@Override
public void connect(ChannelHandlerContext ctx, SocketAddress remoteAddress, SocketAddress localAddress,
                    ChannelPromise promise) throws Exception {

    // Remember the requested remote address for later use.
    final InetSocketAddress inetRemoteAddr = (InetSocketAddress) remoteAddress;
    this.remoteAddress = inetRemoteAddr;

    // Configure the pipeline.
    final Channel ch = ctx.channel();
    ChannelUtil.disableWriterBufferWatermark(ch);

    final ChannelPipeline p = ch.pipeline();
    p.addLast(new FlushConsolidationHandler());
    p.addLast(ReadSuppressingAndChannelDeactivatingHandler.INSTANCE);

    try {
        if (sslCtx != null) {
            configureAsHttps(ch, inetRemoteAddr);
        } else {
            configureAsHttp(ch);
        }
    } catch (Throwable t) {
        promise.tryFailure(t);
        ctx.close();
    } finally {
        if (p.context(this) != null) {
            p.remove(this);
        }
    }

    ctx.connect(remoteAddress, localAddress, promise);
}
 

public final ChannelFuture handshake(Channel channel, boolean sendResponse, ChannelPromise promise) {
  ChannelPipeline p = channel.pipeline();
  ChannelHandlerContext ctx = p.context(RfbClientDecoder.class);
  p.addBefore(ctx.name(), "rfb-security-decoder", newSecurityDecoder());

  ChannelHandlerContext ctx2 = p.context(RfbClientEncoder.class);
  p.addBefore(ctx2.name(), "rfb-security-encoder", newSecurityEncoder());
  if (!sendResponse) {
    return promise.setSuccess();
  }
  channel.writeAndFlush(Unpooled.buffer(1).writeByte(securityType.getType()), promise);
  return promise;
}
 

public void initCodec(IPacketIdCodec packetIdCodec, AbstractPacketEncoder encoder, AbstractPacketDecoder decoder) {
	ChannelPipeline pipeline = networkmanager.getChannel().pipeline();
	this.logicCtx = pipeline.context(ChannelHandlers.LOGIC);
	this.rawSendCtx = pipeline.context(ChannelHandlers.RAW_CAPTURE_SEND);
	this.rawRecvCtx = pipeline.context(ChannelHandlers.RAW_CAPTURE_RECEIVE);
	this.codec = new PacketDataCodecImpl(this, packetIdCodec, pipeline.context(encoder), pipeline.context(decoder));
	encoder.init(codec);
	decoder.init(codec);
}
 

@Override
public void channelRegistered(ChannelHandlerContext channelHandlerContext) throws Exception {
	try {
		initChannel(channelHandlerContext.channel());
	} catch (Throwable t) {
		exceptionCaught(channelHandlerContext, t);
	} finally {
		ChannelPipeline pipeline = channelHandlerContext.pipeline();
		if (pipeline.context(this) != null) {
			pipeline.remove(this);
		}
	}
	channelHandlerContext.pipeline().fireChannelRegistered();
}
 

protected void releaseHandlers(PooledConnection conn) {
    final ChannelPipeline pipeline = conn.getChannel().pipeline();
    removeHandlerFromPipeline(OriginResponseReceiver.CHANNEL_HANDLER_NAME, pipeline);
    // The Outbound handler is always after the inbound handler, so look for it.
    ChannelHandlerContext passportStateHttpClientHandlerCtx =
            pipeline.context(PassportStateHttpClientHandler.OutboundHandler.class);
    pipeline.addAfter(passportStateHttpClientHandlerCtx.name(), IDLE_STATE_HANDLER_NAME,
        new IdleStateHandler(0, 0, connPoolConfig.getIdleTimeout(), TimeUnit.MILLISECONDS));
}
 

/**
 * Validates and finishes the opening handshake initiated by {@link #handshake}}.
 *
 * @param channel
 *            Channel
 * @param response
 *            HTTP response containing the closing handshake details
 */
public final void finishHandshake(Channel channel, FullHttpResponse response) {
    verify(response);

    // Verify the subprotocol that we received from the server.
    // This must be one of our expected subprotocols - or null/empty if we didn't want to speak a subprotocol
    String receivedProtocol = response.headers().get(HttpHeaders.Names.SEC_WEBSOCKET_PROTOCOL);
    receivedProtocol = receivedProtocol != null ? receivedProtocol.trim() : null;
    String expectedProtocol = expectedSubprotocol != null ? expectedSubprotocol : "";
    boolean protocolValid = false;

    if (expectedProtocol.isEmpty() && receivedProtocol == null) {
        // No subprotocol required and none received
        protocolValid = true;
        setActualSubprotocol(expectedSubprotocol); // null or "" - we echo what the user requested
    } else if (!expectedProtocol.isEmpty() && receivedProtocol != null && !receivedProtocol.isEmpty()) {
        // We require a subprotocol and received one -> verify it
        for (String protocol : StringUtil.split(expectedSubprotocol, ',')) {
            if (protocol.trim().equals(receivedProtocol)) {
                protocolValid = true;
                setActualSubprotocol(receivedProtocol);
                break;
            }
        }
    } // else mixed cases - which are all errors

    if (!protocolValid) {
        throw new WebSocketHandshakeException(String.format(
                "Invalid subprotocol. Actual: %s. Expected one of: %s",
                receivedProtocol, expectedSubprotocol));
    }

    setHandshakeComplete();

    ChannelPipeline p = channel.pipeline();
    // Remove decompressor from pipeline if its in use
    HttpContentDecompressor decompressor = p.get(HttpContentDecompressor.class);
    if (decompressor != null) {
        p.remove(decompressor);
    }

    // Remove aggregator if present before
    HttpObjectAggregator aggregator = p.get(HttpObjectAggregator.class);
    if (aggregator != null) {
        p.remove(aggregator);
    }

    ChannelHandlerContext ctx = p.context(HttpResponseDecoder.class);
    if (ctx == null) {
        ctx = p.context(HttpClientCodec.class);
        if (ctx == null) {
            throw new IllegalStateException("ChannelPipeline does not contain " +
                    "a HttpRequestEncoder or HttpClientCodec");
        }
        p.replace(ctx.name(), "ws-decoder", newWebsocketDecoder());
    } else {
        if (p.get(HttpRequestEncoder.class) != null) {
            p.remove(HttpRequestEncoder.class);
        }
        p.replace(ctx.name(),
                "ws-decoder", newWebsocketDecoder());
    }
}