reference:
https://blog.csdn.net/lcuwb/article/details/90705397?utm_source=distribute.pc_relevant.none-task

https://mcxiaoke.gitbooks.io/mqtt-cn/content/mqtt/01-Introduction.html?q=

其他参考：

make install 出现错误, 需要首先make html
https://blog.csdn.net/qudany10061700/article/details/86504294
https://blog.csdn.net/qq_44041062/article/details/96881953
https://blog.csdn.net/herr_kun/article/details/84146462

MQTT :
下载:
https://www.eclipse.org/paho/downloads.php

MQTT app 参考：
https://blog.csdn.net/asjqkkkk/article/details/80714234

apk :实现基本参考下面的例子：
https://www.jianshu.com/p/e1f7ce2989ff

实现方式：
打算在这里启动服务，启动bin 开机启动
external/drm_hwcomposer

Android 环境搭建：
1， jdk 安装
https://blog.csdn.net/bzlj2912009596/article/details/81507642

2， android studio 安装
https://blog.csdn.net/dimo__/article/details/86504274
其中介绍了 UTF-8 需要设定

Protocol Buffer 简介:
https://blog.csdn.net/mzpmzk/article/details/80824839
https://www.jb51.net/article/163871.htm

1， 获取SN
https://blog.csdn.net/HelloWorldRun/article/details/86091163

    public static String getDeviceSN(){
     
        String serialNumber = android.os.Build.SERIAL; 
     
        return serialNumber;
    }

2， 获取frimware

    public String getFirmwareVersion(){
        String firmwareversion =  android.os.Build.VERSION.RELEASE+android.os.Build.BRAND;
        Log.d(TAG, "getFirmwareVersion: "+firmwareversion);
        return firmwareversion;
    }

3，获取电池level
https://developer.android.com/training/monitoring-device-state/battery-monitoring

    /**
     * getBatteryLevel
     */
    public int getBatteryLevel() {
        BatteryManager batteryManager = (BatteryManager)context.getSystemService(BATTERY_SERVICE);
        int battery = batteryManager.getIntProperty(BatteryManager.BATTERY_PROPERTY_CAPACITY);
        Log.d(TAG,"getBatteryLevel: " + battery);
        return battery;
    }

4, 获取充电状态

    /**
     * getChargingState
     */
    public int getChargingState() {
        BatteryManager batteryManager = (BatteryManager)context.getSystemService(BATTERY_SERVICE);
        int status = batteryManager.getIntProperty(BatteryManager.BATTERY_PROPERTY_STATUS);
        Log.d(TAG,"getChargingState:UNKNOWN=1,CHARGING=2,DISCHARGING=3,NOT_CHARGING=4,FULL=5; getstatus=" + status);
        return status;
    }

5.获取IP 地址

    /**
     * getIp
     */
    public long getIp() {
        //获取wifi服务
        WifiManager wifiManager = (WifiManager)context.getSystemService(Context.WIFI_SERVICE);
        //判断wifi是否开启
        if (!wifiManager.isWifiEnabled()) {
            wifiManager.setWifiEnabled(true);
        }
        WifiInfo wifiInfo = wifiManager.getConnectionInfo();
        int ipAddress = wifiInfo.getIpAddress();
        Log.d(TAG, "getIp: " + ipAddress);
        return ipAddress;
    }

获取当前时区：
https://blog.csdn.net/u011974987/article/details/52858085?depth_1-utm_source=distribute.pc_relevant.none-task&utm_source=distribute.pc_relevant.none-task

    public int getCurrentTimeZone() {
        TimeZone tz = TimeZone.getDefault();
        int offsetMinutes = (tz.getRawOffset() / 60000)/60;
        Log.d(TAG, "getCurrentTimeZone: " + offsetMinutes);
        return offsetMinutes;
    }