java 使用mqtt

mqtt的搭建请看https://blog.csdn.net/qq_29350001/article/details/76680646

<dependency>
    <groupId>org.eclipse.paho</groupId>
    <artifactId>mqtt-client</artifactId>
    <version>0.4.0</version>
</dependency>

<!-- https://mvnrepository.com/artifact/org.fusesource.mqtt-client/mqtt-client -->
<dependency>
    <groupId>org.fusesource.mqtt-client</groupId>
    <artifactId>mqtt-client</artifactId>
    <version>1.14</version>
</dependency>

public class MQTTSubscribe implements MqttCallback {


    //public static final String HOST = "tcp://10.0.0.250:1884";
    public static final String HOST = "tcp://127.0.0.1:61613";

    public static final String TOPIC = "gl";
    private static final String clientid = "subscriber";
    private MqttClient client;
    private MqttConnectOptions options;
    private String userName = "admin";
    private String passWord = "password";
    private ScheduledExecutorService scheduler;


    public void startReconnect() {
        scheduler = Executors.newSingleThreadScheduledExecutor();
        scheduler.scheduleAtFixedRate(new Runnable() {
            public void run() {
                if (!client.isConnected()) {
                    try {
                        client.connect(options);
                        System.out.println("重连成功");
                    } catch (MqttSecurityException e) {
                        e.printStackTrace();
                    } catch (MqttException e) {
                        e.printStackTrace();
                    }
                }
            }
        }, 0 * 1000, 10 * 1000, TimeUnit.MILLISECONDS);
    }

    private void start() {
        try {
            client = new MqttClient(HOST, clientid, new MemoryPersistence());
            options = new MqttConnectOptions();
            options.setCleanSession(false);
            options.setUserName(userName);
            options.setPassword(passWord.toCharArray());
            options.setConnectionTimeout(10);
            options.setKeepAliveInterval(20);
            client.setCallback(this);
//            MqttTopic topic = client.getTopic(TOPIC);
//            options.setWill(topic, "close".getBytes(), 2, true);
            client.connect(options);
            int[] Qos = {2};
            String[] topic1 = {TOPIC};
            client.subscribe(topic1, Qos);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


    public static void main(String[] args) throws MqttException {
        MQTTSubscribe client = new MQTTSubscribe();
        client.start();
    }

    public void connectionLost(Throwable cause) {
        startReconnect();
    }

    @Override
    public void deliveryComplete(IMqttDeliveryToken token) {
        try {
            System.out.println("deliveryComplete---------" + token.isComplete());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void messageArrived(String topic, MqttMessage message) throws Exception {
        System.out.println("Message arrived on topic:" + topic);
        System.out.println("Message arrived on QoS:" + message.getQos());
        System.out.println("Message arrived on content:" + new String(message.getPayload()));
    }
}

public class MQTTPublish implements MqttCallback {


    //public static final String HOST = "tcp://10.0.0.250:1884";
    public static final String HOST = "tcp://127.0.0.1:61613";

    public static final String TOPIC = "gl";
    private static final String clientid = "publisher";

    private static final String str = "法国恢复和";
    private static MqttClient client;

    private MqttTopic topic;
    private String userName = "admin";
    private String passWord = "password";

    private MqttMessage message;
    MqttConnectOptions options = new MqttConnectOptions();


    private ScheduledExecutorService scheduler;


    public void startReconnect() {
        scheduler = Executors.newSingleThreadScheduledExecutor();
        scheduler.scheduleAtFixedRate(new Runnable() {
            public void run() {
                if (!client.isConnected()) {
                    try {
                        client.connect(options);
                        System.out.println("重连成功");
                    } catch (MqttSecurityException e) {
                        e.printStackTrace();
                    } catch (MqttException e) {
                        e.printStackTrace();
                    }
                }
            }
        }, 0 * 1000, 10 * 1000, TimeUnit.MILLISECONDS);
    }

    public MQTTPublish() throws MqttException {
        client = new MqttClient(HOST, clientid, new MemoryPersistence());
        connect();
    }

    private void connect() {
        options.setCleanSession(false);
        options.setUserName(userName);
        options.setPassword(passWord.toCharArray());
        options.setConnectionTimeout(10);
        options.setKeepAliveInterval(20);
        try {
            client.setCallback(this);

            client.connect(options);
            topic = client.getTopic(TOPIC);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void publish(MqttMessage message) throws MqttPersistenceException, MqttException {
        MqttDeliveryToken token = topic.publish(message);
        token.waitForCompletion();
        System.out.println("Token is complete:" + token.isComplete());
    }

    public static void main(String[] args) throws MqttException {
        MQTTPublish mqttpub = new MQTTPublish();
        mqttpub.message = new MqttMessage();
        mqttpub.message.setQos(2);//设置qos，决定消息到达次数，如果是1，消息重复的不会到达
        mqttpub.message.setRetained(true);
        mqttpub.message.setPayload(str.getBytes());
        mqttpub.publish(mqttpub.message);
//        System.out.println("Ratained state:" + mqttpub.message.isRetained());
//
//        client.disconnect();
//        System.out.println("Disconnected");
//        System.exit(0);
    }

    @Override
    public void connectionLost(Throwable arg0) {
        startReconnect();
    }

    public void deliveryComplete(IMqttDeliveryToken token) {
        try {
            System.out.println("deliveryComplete---------" + token.isComplete());
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    @Override
    public void messageArrived(String arg0, MqttMessage arg1) throws Exception {
        // TODO Auto-generated method stub

    }
}