/* * Sends a message to the message broker, requesting that it be * published to the specified topic. */ private void publishToTopic(String topicName, String message) throws MqttException { if ((mqttClient == null) || (mqttClient.isConnected() == false)) { // quick sanity check - don't try and publish if we don't have // a connection log("No connection to public to"); } else { mqttClient.publish( topicName, message.getBytes(), MQTT_QUALITY_OF_SERVICE, MQTT_RETAINED_PUBLISH); } }
/* * Send a request to the message broker to be sent messages published * with the specified topic name. Wildcards are allowed. */ private void subscribeToTopic(String topicName) throws MqttException { if ((mqttClient == null) || (mqttClient.isConnected() == false)) { // quick sanity check - don't try and subscribe if we don't have // a connection log("Connection error" + "No connection"); } else { String[] topics = {topicName}; mqttClient.subscribe(topics, MQTT_QUALITIES_OF_SERVICE); } }