Implementation of the client part of the MQTT protocol

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Get Started

1. Dependency

   • Maven

     Add Jcenter repository first

     <repository>
         <id>jcenter</id>
         <name>jcenter</name>
         <url>https://jcenter.bintray.com</url>
     </repository>

     then

     <dependency>
         <groupId>com.dreamgyf.mqtt</groupId>
         <artifactId>gmqyttf-client</artifactId>
         <version>0.1.0</version>
         <type>pom</type>
     </dependency>

   • Gradle

     Add Jcenter repository first

     repositories {
       jcenter()
     }

     then

     implementation 'com.dreamgyf.mqtt:gmqyttf-client:0.1.0'

2. Run

   //Build client first
   MqttClient client = new MqttClient.Builder()
      .cleanSession(true)
      .clientId("test1")
      .usernameFlag(true)
      .passwordFlag(true)
      .username("dreamgyf")
      .password("dreamgyf")
      .keepAliveTime((short) 10)
      .willFlag(true)
      .willQoS(2)
      .willTopic("/willTopic")
      .willMessage("")
      .willRetain(true)
      .build(MqttVersion.V3_1_1);
   
   //Set callback
   client.setCallback(new MqttClientCallback() {
       @Override
       public void onConnectSuccess() {
           System.out.println("Connection success");
       }
   
       @Override
       public void onConnectionException(MqttException e) {
           e.printStackTrace();
           System.err.println("Connection exception: " + e + " " + e.getMessage());
       }
   
       @Override
       public void onSubscribeFailure(MqttTopic mqttTopic) {
           System.err.println("Subscription failed: " + mqttTopic.getTopic() + " QoS: " + mqttTopic.getQoS());
       }
   
       @Override
       public void onMessageReceived(String topic, String message) {
           System.out.println("Message received, topic: " + topic + " message: " + message);
       }
   });
   
   //Connect,subscribe,publish
   client.connect("broker.emqx.io", 1883);
   
   client.subscribe(new MqttTopic("/dreamgyf/test", 2));
   client.publish("/dreamgyf/test", "publish test", new MqttPublishOption().QoS(2));