@Test
  public void saveDatenbasis() throws IOException {
    Datenbasis datenbasis = new Datenbasis();
    datenbasis.setVersionInfo(ANY_VERSION_INFORMATION);
    List<Register> registerList = createRegisterList();
    datenbasis.setRegisterList(registerList);

    datenbasisFactory.saveData(dataOutputFacade, datenbasis);

    verify(dataOutputFacade).writeString(ANY_VERSION_INFORMATION);
    verify(dataOutputFacade).writeInt(registerList.size());
    verify(registerFactory).saveData(dataOutputFacade, registerList.get(0));
    verify(registerFactory).saveData(dataOutputFacade, registerList.get(1));
  }