@Override
    public List<String> getColumnNames(String tableName, String datasource) {
        DatabaseMetaData metaData = null;
        List<String> columnNames = Lists.newArrayList();
        ResultSet rs = null;
        try {
            metaData = conn.getMetaData();
            rs = metaData.getColumns(conn.getCatalog(), null, tableName, "%");
            while (rs.next()) {
                columnNames.add(rs.getString("COLUMN_NAME"));
                // 获取字段的数据类型  rs.getString("TYPE_NAME")
            }

        } catch (SQLException e) {
            logger.error("[getColumnNames Exception] --> "
                    + "the exception message is:" + e.getMessage());
        } finally {
            JdbcUtils.close(rs);
        }


        return columnNames;
    }
@Test
    public void getColumnNames() {
        List<String> columns = queryTool.getColumnNames("STOCK_SYMBOL", null);

        for (String column : columns) {
            System.out.println(column);
        }
    }