MQTT（Message Queue Telemetry Transport，即消息隊列遙測傳輸協議）是一種輕量級的消息傳輸協議，主要用于物聯網設備或低帶寬網絡環境下的通信。MQTT協議中包含三個主要組件：客戶端、消息代理（Broker）和訂閱（Subscription）。

AMQP（Advanced Message Queuing Protocol，即高級消息隊列協議）是一種傳輸協議，主要用于分布式消息傳輸。AMQP協議定義了一套消息格式以及客戶端與Broker之間的通信規則，支持多語言和多平臺的使用。

//MQTT示例代碼
MqttClient client = new MqttClient(brokerUrl, clientId);
MqttConnectOptions connOpt = new MqttConnectOptions();
connOpt.setCleanSession(true);
client.connect(connOpt);
//發布消息
MqttMessage message = new MqttMessage(content.getBytes());
message.setQos(qos);
client.publish(topic, message);
//訂閱消息
client.subscribe(topic);
client.setCallback(new MqttCallback() {
public void connectionLost(Throwable cause) {
}
public void messageArrived(String topic, MqttMessage message) throws Exception {
//處理接收到的消息
}
public void deliveryComplete(IMqttDeliveryToken token) {
}
});

//AMQP示例代碼
ConnectionFactory connectionFactory = new ConnectionFactory();
connectionFactory.setHost(hostName);
Connection connection = connectionFactory.newConnection();
//創建通道
Channel channel = connection.createChannel();
channel.exchangeDeclare(exchangeName, "direct");
//發送消息
channel.basicPublish(exchangeName, routingKey, null, message.getBytes());
//接收消息
channel.queueDeclare(queueName, false, false, false, null);
channel.queueBind(queueName, exchangeName, routingKey);
channel.basicConsume(queueName, new DefaultConsumer(channel) {
public void handleDelivery(String consumerTag, Envelope envelope, AMQP.BasicProperties properties, byte[] body) throws IOException {
String message = new String(body, "UTF-8");
//處理接收到的消息
}
});