code: private int compareToLabel(int currentResult, VersionIdentifier otherVersion) {
  
      if (currentResult == COMPARE_TO_INCOMPARABLE) {
        return COMPARE_TO_INCOMPARABLE;
      }
      int result = currentResult;
      if (result == 0) {
        String label = getLabel();
        if (label != null) {
          String otherLabel = otherVersion.getLabel();
          if (otherLabel != null) {
            if (!label.equalsIgnoreCase(otherLabel)) {
              // 2 versions identical except for label
              return COMPARE_TO_INCOMPARABLE;
            }
          }
        }
      }
      return result;
    }
docs: This method performs the part of {@link #compareTo(VersionIdentifier)} for the {@link #getLabel() label}.
  
  @param currentResult is the current result so far.
  @param otherVersion is the {@link VersionIdentifier} to compare to.
  @return the result of comparison.