String (@NotNull Matcher matcher) { final String preReleaseType = matcher.group(PRE_RELEASE_TYPE_GROUP); if (preReleaseType != null) { final String preReleaseNumber = matcher.group(PRE_RELEASE_NUMBER_GROUP); final String normalizedPreReleaseNumber = preReleaseNumber == null ? "0" : normalizeNumber(preReleaseNumber); return normalizePreReleaseType(preReleaseType) + normalizedPreReleaseNumber; } return null; }