code: public static boolean checkService(Context context, Class<?> service) {
      try {
        ServiceInfo info = context.getPackageManager().getServiceInfo(
            new ComponentName(context, service), 0);
        return null != info;
      } catch (PackageManager.NameNotFoundException e) {
        printErrorLog("service " + service.getName() + " is missing!");
        return false;
      }
    }
docs: 判断 Mainifest 中是否包含对应到 Service
  如有，则返回 true，反之，则返回 false 并输出日志
  
  @param context
  @param service
  @return