Used Software in this talk: HiveMQ MQTT Server - http://www.hivemq.com Paho - http://www.eclipse.org/paho/ Mobile devices like smartphones and tablet computers became an integral part of our modern world and single-board computers like Raspberry Pi are cheaper today than at any time before. Simple and open Machine-to-Machine (M2M) protocols like MQTT enable these devices to communicate in an efficient manner, even in scenarios with unreliable und instable networks. This talk shows how Eclipse Paho - an Eclipse umbrella project for M2M protocols - can be utilized for professional and personal projects to build efficient and scalable solutions for (mobile) devices.

1. M2M for Java Developers
MQTT with Eclipse Paho
17-07-2013 -- #democampstuttgart
Dominik Obermaier -- dc-square GmbH

2. Dominik Obermaier
@dobermai
MQTT Enthusiast
loves OSS
passionate
Architect & Maker
Co-Founder dc-square
likes Open Source Hardware

3. Dominik Obermaier
@dobermai
MQTT Enthusiast
loves OSS
passionate
Architect & Maker
Co-Founder dc-square
likes Open Source Hardware
K Who not?!?

4. M2M?

5. TECHNOLOGY THAT
SUPPORTS WIRED
OR WIRELESS
COMMUNICATION
BETWEEN DEVICES

6. Why
should
we
care?

7. 2010 2015 2020
~6.909.000.000 ~7.302.000.000 ~7.675.000.000
~12.500.000.000 ~25.000.000.000 ~50.000.000.000
[1]Source: http://www.un.org/esa/population/publications/wpp2008/wpp2008_highlights.pdf
[1]
[2]Source: http://share.cisco.com/internet-of-things.html
[2]
“Things” in the Internet

8. Things?

17. Which
protocol
?

19. Why MQTT?
✓ Simple
✓ Efficient
✓ Publish / Subscribe
✓ Quality of Service Levels
✓ Last Will and Testament
✓ Designed for unreliable networks

20. Why MQTT?
✓ Simple
✓ Efficient
✓ Publish / Subscribe
✓ Quality of Service Levels
✓ Last Will and Testament
✓ Designed for unreliable networks
KWireless? Yep, then it probably is unreliable

21. Publish / Subscribe

22. OMG! Sounds like
programming in C!

24. What
about
Java?

26. What is Paho?
✓ Scalable Open Source Implementations of M2M
standard protocols
✓ Focus on MQTT
✓ Implementations in Java, Javascript, Lua and C
✓ Eclipse Incubator

27. What is Paho?
✓ Scalable Open Source Implementations of M2M
standard protocols
✓ Focus on MQTT
✓ Implementations in Java, Javascript, Lua and C
✓ Eclipse Incubator
KRead: What is Paho at the moment

28. Code!
public void start() throws Exception {
final String clientId = "eclipse_stuttgart_sub";
final MqttClient mqttClient = new MqttClient(BROKER_URL,
clientId, new MemoryPersistence());
mqttClient.setCallback(new SubscribeCallback(mqttClient));
mqttClient.connect();
mqttClient.subscribe(TOPIC_SUBSCRIPTION,
QUALITY_OF_SERVICE_LEVEL);
}

29. Moar Code!
public class SubscribeCallback implements MqttCallback {
@Override
public void connectionLost(Throwable cause) {}
@Override
public void deliveryComplete(MqttDeliveryToken token) {}
@Override
public void messageArrived(MqttTopic topic,
MqttMessage message)
throws Exception {
System.out.println("Message arrived. Topic: "
topic.getName() + ", QoS: " + message.getQos() +
", message: " + new String(message.getPayload(),
Charset.forName("UTF-8")));
}
}

30. DEMO!

31. Other Eclipse
M2M Projects

32. Credits
✓ Scared Cat Picture by http://www.flickr.com/photos/
dat-pics/
✓ Thanks Vincent Le Moign for the awesome Icon Set
✓ Rest of pictures licensed from different people from
500px.com
✓ MQTT Logo by http://www.mqtt.org