String sql = "select a.name  from (select u.name , u.age from user u inner join alert al on alert.id = user.id)  a";

//            String sql = "select c.a as e,c.b from (select a,count(*) b from alert) c";
//        String sql = "select a.name c from alert a";
//        SQLExprParser exprParser = SQLParserUtils.createExprParser(sql, "mysql");
        List<SQLStatement> sqlStatements = SQLUtils.parseStatements(sql, JdbcConstants.MYSQL);
        SchemaStatVisitor statVisitor = SQLUtils.createSchemaStatVisitor(JdbcConstants.MYSQL);
        sqlStatements.get(0).accept(statVisitor);
        Collection<TableStat.Column> columns = statVisitor.getColumns();
        for (TableStat.Column column : columns) {
            if (column.isSelect()) {
                System.out.println(column.toString());
            }
        }

结果
user.name user.age

团队能提供select属性出现的位置吗，比如我只需要获取最外层的user.name;