public static void main()

in mqtt-example/src/main/java/org/apache/rocketmq/mqtt/example/MqttProducer.java [36:94]
54 lines of code
3 McCabe index (conditional complexity)

    public static void main(String[] args) throws InterruptedException, MqttException, NoSuchAlgorithmException, InvalidKeyException {
        MemoryPersistence memoryPersistence = new MemoryPersistence();
        String brokerUrl = "tcp://" + System.getenv("host") + ":1883";
        String firstTopic = System.getenv("topic");
        String sendClientId = "send01";
        MqttConnectOptions mqttConnectOptions = buildMqttConnectOptions(sendClientId);
        MqttClient mqttClient = new MqttClient(brokerUrl, sendClientId, memoryPersistence);
        mqttClient.setTimeToWait(5000L);
        mqttClient.setCallback(new MqttCallbackExtended() {
            @Override
            public void connectComplete(boolean reconnect, String serverURI) {
                System.out.println(sendClientId + " connect success to " + serverURI);
            }

            @Override
            public void connectionLost(Throwable throwable) {
                throwable.printStackTrace();
            }

            @Override
            public void messageArrived(String topic, MqttMessage mqttMessage) {
            }

            @Override
            public void deliveryComplete(IMqttDeliveryToken iMqttDeliveryToken) {
            }
        });
        try {
            mqttClient.connect(mqttConnectOptions);
        } catch (Exception e) {
            e.printStackTrace();
        }
        long interval = 1000;
        for (int i = 0; i < 1000; i++) {
            String msg = "r1_" + System.currentTimeMillis() + "_" + i;
            MqttMessage message = new MqttMessage(msg.getBytes(StandardCharsets.UTF_8));
            message.setQos(1);
            String mqttSendTopic = firstTopic + "/r1";
            mqttClient.publish(mqttSendTopic, message);
            System.out.println(now() + "send: " + mqttSendTopic + ", " + msg);
            Thread.sleep(interval);

            mqttSendTopic = firstTopic + "/r/wc";
            msg = "wc_" + System.currentTimeMillis() + "_" + i;
            MqttMessage messageWild = new MqttMessage(msg.getBytes(StandardCharsets.UTF_8));
            messageWild.setQos(1);
            mqttClient.publish(mqttSendTopic, messageWild);
            System.out.println(now() + "send: " + mqttSendTopic + ", " + msg);
            Thread.sleep(interval);

            mqttSendTopic = firstTopic + "/r2";
            msg = "msgQ2_" + System.currentTimeMillis() + "_" + i;
            message = new MqttMessage(msg.getBytes(StandardCharsets.UTF_8));
            message.setQos(2);
            mqttClient.publish(mqttSendTopic, message);
            System.out.println(now() + "send: " + mqttSendTopic + ", " + msg);
            Thread.sleep(interval);
        }
    }