#vulnerable code 
                              private Customer convertPersistableCustomerToCustomer(PersistableCustomer customer, MerchantStore store) {

    Customer cust = new Customer();

    CustomerPopulator populator = new CustomerPopulator();
    populator.setCountryService(countryService);
    populator.setCustomerOptionService(customerOptionService);
    populator.setCustomerOptionValueService(customerOptionValueService);
    populator.setLanguageService(languageService);
    populator.setLanguageService(languageService);
    populator.setZoneService(zoneService);
    populator.setGroupService(groupService);
    try{
      populator.populate(customer, cust, store, store.getDefaultLanguage());
    } catch (ConversionException e) {
      throw new ConversionRuntimeException(e);
    }


    List<Group> groups = getListOfGroups(GroupType.CUSTOMER);
    cust.setGroups(groups);

    Locale customerLocale = LocaleUtils.getLocale(cust.getDefaultLanguage());

    String password = customer.getClearPassword();
    if (StringUtils.isBlank(password)) {
      password = UserReset.generateRandomString();
      customer.setClearPassword(password);
    }

    @SuppressWarnings("deprecation")
    String encodedPassword = passwordEncoder.encode(password);
    if (!StringUtils.isBlank(customer.getEncodedPassword())) {
      encodedPassword = customer.getEncodedPassword();
      // customer.setClearPassword("");
    }

    cust.setPassword(encodedPassword);

    return cust;

  } 
                            #location 23 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                              private Customer convertPersistableCustomerToCustomer(PersistableCustomer customer, MerchantStore store) {

    Customer cust = new Customer();

    CustomerPopulator populator = new CustomerPopulator();
    populator.setCountryService(countryService);
    populator.setCustomerOptionService(customerOptionService);
    populator.setCustomerOptionValueService(customerOptionValueService);
    populator.setLanguageService(languageService);
    populator.setLanguageService(languageService);
    populator.setZoneService(zoneService);
    populator.setGroupService(groupService);
    try{
      populator.populate(customer, cust, store, store.getDefaultLanguage());
    } catch (ConversionException e) {
      throw new ConversionRuntimeException(e);
    }


    List<Group> groups = getListOfGroups(GroupType.CUSTOMER);
    cust.setGroups(groups);

    String password = customer.getClearPassword();
    if (StringUtils.isBlank(password)) {
      password = UserReset.generateRandomString();
      customer.setClearPassword(password);
    }


    String encodedPassword = passwordEncoder.encode(password);
    if (!StringUtils.isBlank(customer.getEncodedPassword())) {
      encodedPassword = customer.getEncodedPassword();
      // customer.setClearPassword("");
    }

    cust.setPassword(encodedPassword);

    return cust;

  }