public BluetoothGattCharacteristic getCharacteristic(UUID uuid) {
        for (BluetoothGattCharacteristic characteristic : mCharacteristics) {
            if (uuid.equals(characteristic.getUuid())) {
                return characteristic;
            }
        }
        return null;
    }
Used for mocks and constants in rxandroidble, but instances created in mockrxandroidble, so the methods must be implemented
rxandroidble/src/test/java/android/bluetooth/BluetoothGattService.java