code: public Token getNextToken(final String logFormat, final int startOffset) {
          final int pos = logFormat.indexOf(logFormatToken, startOffset);
          if (pos == -1) {
              return null;
          }
  
          Token token = new Token(
                  regex,
                  pos,
                  logFormatToken.length(),
                  prio)
              .addOutputFields(outputFields);
  
          if (warningMessageWhenUsed != null) {
              token.setWarningMessageWhenUsed(warningMessageWhenUsed);
          }
  
          if (!addCustomDissector(token,
              outputFields.get(0).getType(),
              outputFields.get(0).getName())) {
              return null;
          }
  
          return token;
      }
docs: --------------------------------------------