getDefaultAdapter(); Deprecation

I use

BluetoothAdapter bluetooth = BluetoothAdapter.getDefaultAdapter();

in my code to be able to connect with Bluetooth, but unfortunately, this code is already a deprecated method. It still works but I don’t know if it would still be reliable in the future.

So due to this, I tried this code in exchange of the deprecated code above. I use

final BluetoothManager mBluetoothManager = (BluetoothManager) getActivity().getSystemService(Context.BLUETOOTH_SERVICE);
BluetoothAdapter bluetooth = mBluetoothManager.getAdapter();

but unfortunately, this code crashes.

Any solutions/alternatives for the deprecated code? Or is it ok to use the deprecated code in future developments?