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private void scanLeDevices() {
  localIPs.clear();
  localHostnames.clear();
  if (!(mBluetoothAdapter == null) && mBluetoothAdapter.isEnabled()) {
    if (ActivityCompat.checkSelfPermission(this.connectionContext, android.Manifest.permission.BLUETOOTH_CONNECT) != PackageManager.PERMISSION_GRANTED) {
      // TODO: Consider calling
      //    ActivityCompat#requestPermissions
      // here to request the missing permissions, and then overriding
      //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
      //                                          int[] grantResults)
      // to handle the case where the user grants the permission. See the documentation
      // for ActivityCompat#requestPermissions for more details.

      System.out.println("BLUETOOTH_CONNECT not granted?!?!?");
      return;
    }
    // retrieve bonded devices ( even if a new device is connected via BT is paired )
    //mBluetoothAdapter.cancelDiscovery();
    Set<BluetoothDevice> bluetoothSet = mBluetoothAdapter.getBondedDevices();
    if (bluetoothSet.size() > 0) {
      for (BluetoothDevice device : bluetoothSet) {
        localIPs.add(device.getAddress());
        localHostnames.add(device.getName());

        System.out.println("All paired checked?");
      }
    }

    if (!localIPs.isEmpty() && localIPs.size() > 0) {
      //bluetoothSet.forEach((BluetoothDevice device) -> {
      //    ParcelUuid[] deviceUuids = device.getUuids();  <--- multiple device uids for single remote device?
      //    mBluetoothSocket = device.createRfcommSocketToServiceRecord(deviceUuids);
      //});
      try {
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.Q) {
          BluetoothServerSocket mServerSocket = mBluetoothAdapter.listenUsingInsecureL2capChannel();
          psm = mServerSocket.getPsm();
        }
        IntStream.range(0, localIPs.size())
            .forEach(i -> {
                BluetoothDevice device = mBluetoothAdapter.getRemoteDevice(localIPs.get(i));
                //mBluetoothSocket = device.createInsecureRfcommSocketToServiceRecord(UUID.fromString(Constants.STR_UUID));
                if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.Q) {
                  try {
                    mBluetoothSocket = device.createL2capChannel(psm);
                    if (!mBluetoothSocket.isConnected())
                      try {
                        mBluetoothSocket.connect();
                      } catch(IOException e) {
                        e.printStackTrace();
                      }
                    else
                      System.out.println("Is Connected!!!");
                  } catch (IOException e) {
                    throw new RuntimeException(e);
                  }
                }
            });
      } catch (IOException e) {
        e.printStackTrace();
      }
    }


  }
}