io.netty.handler.codec.mqtt.MqttMessageType # PUBLISH 源码实例Demo

public static MqttPublishMessage getPubMessage(Message message,boolean dup,int qos,int messageId){
    MqttFixedHeader fixedHeader = new MqttFixedHeader(MqttMessageType.PUBLISH,dup,MqttQoS.valueOf(qos),false,0);
    MqttPublishVariableHeader publishVariableHeader = new MqttPublishVariableHeader((String) message.getHeader(MessageHeader.TOPIC),messageId);
    ByteBuf heapBuf;
    if(message.getPayload() == null){
        heapBuf = Unpooled.EMPTY_BUFFER;
    }else{
        heapBuf = Unpooled.wrappedBuffer((byte[])message.getPayload());
    }
    return new MqttPublishMessage(fixedHeader,publishVariableHeader,heapBuf);
}
 

private MqttPublishMessage createMqttPublishMsg(DeviceSessionCtx ctx, String topic, JsonElement json) {
  MqttFixedHeader mqttFixedHeader = new MqttFixedHeader(MqttMessageType.PUBLISH, false, MqttQoS.AT_LEAST_ONCE, false,
      0);
  MqttPublishVariableHeader header = new MqttPublishVariableHeader(topic, ctx.nextMsgId());
  ByteBuf payload = ALLOCATOR.buffer();
  payload.writeBytes(GSON.toJson(json).getBytes(UTF8));
  return new MqttPublishMessage(mqttFixedHeader, header, payload);
}
 

protected void send(int messageId, String topicName, int qosLevel, boolean isRetain, ByteBuf payload, int deliveryCount) {
   boolean redelivery = qosLevel == 0 ? false : (deliveryCount > 0);
   MqttFixedHeader header = new MqttFixedHeader(MqttMessageType.PUBLISH, redelivery, MqttQoS.valueOf(qosLevel), isRetain, 0);
   MqttPublishVariableHeader varHeader = new MqttPublishVariableHeader(topicName, messageId);
   MqttMessage publish = new MqttPublishMessage(header, varHeader, payload);
   sendToClient(publish);
}
 

public void publish2Subscriber(String name, String clientID, MqttSession session, Consumer consumer, int qos) throws Exception {
    PullResult result = consume.getMessage(
            consumer,
            1,
            1000 * 60 * 2
    );
    String topicName = result.getTopic();
    List<ByteBuffer> buffers = result.getBuffers();
    if (buffers != null && buffers.size() > 0) {
        BrokerMessage brokerMessage = Serializer.readBrokerMessage(buffers.get(0));
        MqttFixedHeader mqttFixedHeader = new MqttFixedHeader(
                MqttMessageType.PUBLISH,
                false,
                MqttQoS.valueOf(MqttMessageSerializer.getLowerQos(MqttMessageSerializer.readExtension(brokerMessage), qos)),
                false,
                0
        );
        int packageId = session.getMessageAcknowledgedZone().acquireAcknowledgedPosition(brokerMessage);
        MqttPublishMessage publishMsg = (MqttPublishMessage) MqttMessageFactory.newMessage(
                mqttFixedHeader,
                new MqttPublishVariableHeader(topicName, packageId),
                Unpooled.wrappedBuffer(brokerMessage.getByteBody()));

        boolean isActive = connectionManager.isConnected(clientID);
        if (isActive) {
            MqttConnection connection = connectionManager.getConnection(clientID);
            Channel channel = connection.getChannel();
            if (channel.isActive() && channel.isOpen()) {
                channel.writeAndFlush(publishMsg).addListener((ChannelFutureListener) channelFuture -> {
                    if (channelFuture.isSuccess()) {
                        if (LOG.isDebugEnabled()) {
                            LOG.debug("推送消息成功: {}", publishMsg);
                        }
                    } else {
                        LOG.error("publish message error, thread: <{}>, clientID: <{}>, message: <{}>, cause: <{}>", name, clientID, brokerMessage, channelFuture.cause());
                        throw new Exception(channelFuture.cause());
                    }
                });
            }
        }
    }
}
 

@Override
public MqttMessageType type() {
    return MqttMessageType.PUBLISH;
}
 

public static MqttPublishMessage publish(IMessage message, boolean isDup) {
	MqttFixedHeader fixedHeader = new MqttFixedHeader(MqttMessageType.PUBLISH, isDup, message.qos(),
			message.isRetain(), 7 + message.message().length);

	MqttPublishVariableHeader variableHeader = new MqttPublishVariableHeader(message.topicName(), message.id());

	ByteBuf buf = PooledByteBufAllocator.DEFAULT.buffer(message.message().length);

	return new MqttPublishMessage(fixedHeader, variableHeader, buf.writeBytes(message.message()));
}
 

private MqttPublishMessage createPublishMessage() {

    MqttFixedHeader mqttFixedHeader =
      new MqttFixedHeader(MqttMessageType.PUBLISH, false, MqttQoS.AT_LEAST_ONCE, true, 0);

    MqttPublishVariableHeader mqttPublishVariableHeader = new MqttPublishVariableHeader(MQTT_TOPIC, 1);

    ByteBuf payload =  ALLOCATOR.buffer();
    payload.writeBytes(MQTT_MESSAGE.getBytes(CharsetUtil.UTF_8));

    return new MqttPublishMessage(mqttFixedHeader, mqttPublishVariableHeader, payload);
  }