April 2017
Intermediate to advanced
280 pages
6h 18m
English
Content preview from MQTT Essentials - A Lightweight IoT ProtocolBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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Working with asynchronous notifications and callbacks in Java
The following lines continue the declaration of the public static main method. The code file for the sample is included in the mqtt_essentials_gaston_hillar_04 folder, in the Java01/src/Main.java file:
mqttAsyncClient.setCallback(new MqttCallback() { @Override public void connectionLost(Throwable cause) { cause.printStackTrace(); } @Override public void deliveryComplete(IMqttDeliveryToken token) { } @Override public void messageArrived(String topic, MqttMessage message) throws Exception { if (!topic.equals(topic_for_led01)) { return; } String messageText = new String(message.getPayload(), "UTF-8"); System.out.println( String.format("Topic: %s. Payload: %s", topic, messageText)); } }); ...Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
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