SubscriptionManagerCompat.java 文件源码

public Optional<SubscriptionInfoCompat> getActiveSubscriptionInfo(int subscriptionId) {
  if (Build.VERSION.SDK_INT < 22) {
    return Optional.absent();
  }

  SubscriptionInfo subscriptionInfo = SubscriptionManager.from(context).getActiveSubscriptionInfo(subscriptionId);

  if (subscriptionInfo != null) {
    return Optional.of(new SubscriptionInfoCompat(subscriptionId, subscriptionInfo.getDisplayName(),
                                                  subscriptionInfo.getMcc(), subscriptionInfo.getMnc()));
  } else {
    return Optional.absent();
  }
}