private Token parseIso8601DelimiterToken(String candidate, boolean fillMode, int begin) {
    checkFillModeOff(fillMode, begin);
    Token lastAddedToken;
    lastAddedToken = new Token(TokenType.ISO_8601_DELIMITER, candidate.toUpperCase());
    tokens.add(lastAddedToken);
    return lastAddedToken;
  }
Parse pattern to list of tokens.
common/src/java/org/apache/hadoop/hive/common/format/datetime/HiveSqlDateTimeFormatter.java