code: public SqlBuilder builder() {
          List<IRuleParser> sqlRuleParsers = new ArrayList<>();
          for (IRuleParser parser : ruleParsers) {
              if (parser instanceof AbstractSqlRuleParser) {
                  sqlRuleParsers.add(parser);
              }
          }
          return new SqlBuilder(groupParser, sqlRuleParsers, filters);
      }
docs: 获取builder
  @return