java利用反射原理：根据某个对象的名称和方法去执行该方法。

/**
 * 用反射得到系统隐藏api 读取系统属性
 * @param key
* @return
*/
public static String getPropertyReflect(String key) {

   // reflect call system properties
   Class osSystem = null;
   try {
      osSystem = Class.forName("android.os.SystemProperties");
      Method getDeviceIDMethod = osSystem.getMethod("get",
            new Class[] { String.class });
      String tv2deviceid = (String) getDeviceIDMethod.invoke(osSystem,
            new Object[] { key });
      if (tv2deviceid != null && tv2deviceid.length() > 0) {

         Log.d(TAG, key + " = " + tv2deviceid);
         return tv2deviceid;
      }

   } catch (Exception e1) {
      e1.printStackTrace();
   }

   return "";
}