#vulnerable code 
                              public ConfigurationSettingCsvFile getValues() {
    if (this.listbox.getSelectedValue().equals("--")) {
      this.messageReceiver.addError("You must choose a CSV file!");
      return null;
    }

    FileInput currentFileInput = this.fileInputs.get(
        this.listbox.getSelectedValue());

    return getCurrentSetting(currentFileInput);
  } 
                            #location 2 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                              public ConfigurationSettingCsvFile getValues() throws InputValidationException {
    String selectedValue = this.listbox.getSelectedValue();

    if (selectedValue.equals("--")) {
      throw new InputValidationException("You must choose a CSV file!");
    }

    FileInput currentFileInput = this.fileInputs.get(selectedValue);

    return getCurrentSetting(currentFileInput);
  }