code: private String toBuildNumberString() {
  
      int buildNumber = getBuildNumber();
  
      return (buildNumber > 0 ? String.format(" build %d", buildNumber) : StringUtils.EMPTY_STRING);
    }
docs: Returns a {@link String} containing the software build number for this {@link Version}.
  
  @return a {@link String} containing the software build number for this {@link Version}, or an empty {@link String}
  if the software build number was unspecified.
  @see #getBuildNumber()