How to Subscribe Multiple topic and Multiple MqttCallback Using PAHO on Java
<pre><code>static String[] meandgroup = new String[]{"timentask/c/u000000000005", "timentask/c/u0000000GRP85", "timentask/c/u000000GRP107", "timentask/c/u0000000GRP84", "timentask/c/u000000GRP100"};
    public static List&lt;MqttClient&gt; mqttConnect(Object topicId) {
        try {
            mqttClient = new ArrayList&lt;MqttClient&gt;();
            for (int i = 0; i &lt; meandgroup.length; i++) {
                //if (mqttClient.get(i) == null || !mqttClient.get(i).isConnected()){
                if (!globalData.GlobalDataSetGet.MQTT_SERVER_HOST_NAME.equals("") &amp;&amp; !globalData.GlobalDataSetGet.MQTT_SERVER_USER_NAME.equals("")) {
                    String topicName = meandgroup[i];
                    mqttClient.add(MqttMgr.subscriber(globalData.GlobalDataSetGet.MQTT_SERVER_HOST_NAME,
                            globalData.GlobalDataSetGet.MQTT_SERVER_PORT_NUMBER, globalData.GlobalDataSetGet.MQTT_SERVER_USER_NAME,
                            globalData.GlobalDataSetGet.MQTT_SERVER_USER_PASSWORD, Constants.MQTT_CONNECTION_KEEP_ALIVE_SECS, topicName, "client" + globalData.GlobalDataSetGet.getUserIdValue, new ChatPaneWrite()));
                }
            }
        } catch (MqttException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
        return mqttClient;
    }
</code></pre>