User storage SPI

Getting advice
1

Hello. I am trying to integrate keycloak into our application. We got legacy user database which we want to migrate into keycloak with import strategy. But I got problem in step where I want to create credential for new user in keycloak database. I just edited quickstart example. I am trying to set new password for user from input on lines 263-265 https://github.com/radovans/Keycloak-problem/blob/master/src/main/java/org/keycloak/quickstart/writeable/PropertyFileUserStorageProvider.java but nothing works. Can you help me please? I am using keycloak 8.0.1. Thank you in advance