gistfile1.txt

    // Minimize the execution scope of new user thread.
    // Most code still run in UI thread, except isBillingSupported.
    // Ensure user thread doesn't deal with member variable.
    
    @Override
    public void onServiceConnected(ComponentName name, IBinder service) {
      BillingHelper.logVerbose(TAG, "Billing service connected.");

      mService = IInAppBillingService.Stub.asInterface(service);
      String packageName = mApplicationContext.getPackageName();

      executeAsync(() -> {
        try {
          IInAppBillingService _service = mService;
          if (_service == null) {
            return;
          }

          int _responseForSubs = BillingResponse.BILLING_UNAVAILABLE;
          int _responseFoInApp = BillingResponse.BILLING_UNAVAILABLE;
          // Determine the highest supported level for Subs.
          int _highestLevelSupportedForSubs = 0;
          // Determine the highest supported level for InApp.
          int _highestLevelSupportedForInApp = 0;

          for (int apiVersion = MAX_IAP_VERSION; apiVersion >= MIN_IAP_VERSION; apiVersion--) {
            _responseForSubs = _service.isBillingSupported(apiVersion, packageName, SkuType.SUBS);
            if (_responseForSubs == BillingResponse.OK) {
              _highestLevelSupportedForSubs = apiVersion;
              break;
            }
          }

          for (int apiVersion = MAX_IAP_VERSION; apiVersion >= MIN_IAP_VERSION; apiVersion--) {
            _responseFoInApp = _service.isBillingSupported(apiVersion, packageName, SkuType.INAPP);
            if (_responseFoInApp == BillingResponse.OK) {
              _highestLevelSupportedForInApp = apiVersion;
              break;
            }
          }

          final int highestLevelSupportedForSubs = _highestLevelSupportedForSubs;
          final int highestLevelSupportedForInApp = _highestLevelSupportedForInApp;
          final int responseForSubs = _responseForSubs;
          final int responseFoInApp = _responseFoInApp;

          // Now, switch back to UI thread, to minimize possible side effect.
          postToUiThread(() -> {
            mSubscriptionUpdateSupported = highestLevelSupportedForSubs >= 5;
            mSubscriptionsSupported = highestLevelSupportedForSubs >= 3;
            if (highestLevelSupportedForSubs < MIN_IAP_VERSION) {
              BillingHelper.logVerbose(
                      TAG, "In-app billing API does not support subscription on this device.");
            }

            mIABv8Supported = highestLevelSupportedForInApp >= 8;
            mIABv6Supported = highestLevelSupportedForInApp >= 6;
            if (highestLevelSupportedForInApp < MIN_IAP_VERSION) {
              BillingHelper.logWarn(
                      TAG, "In-app billing API version 3 is not supported on this device.");
            }

            if (responseForSubs == BillingResponse.OK && responseFoInApp == BillingResponse.OK) {
              mClientState = ClientState.CONNECTED;
            } else {
              mClientState = ClientState.DISCONNECTED;
              mService = null;
            }
            // Pick bad response if any.
            mListener.onBillingSetupFinished(responseForSubs != BillingResponse.OK ? responseForSubs : responseFoInApp);
          });
        } catch (final RemoteException e) {
          postToUiThread(() -> {
            BillingHelper.logWarn(TAG, "RemoteException while setting up in-app billing" + e);
            mClientState = ClientState.DISCONNECTED;
            mService = null;
            mListener.onBillingSetupFinished(BillingResponse.SERVICE_DISCONNECTED);
          });
        }
      });
    }