将JDBC ResultSet结果集转成List

private static List<List<Object>> list = new ArrayList<List<Object>>();  
    public static String queryAll() {  
        Connection conn = null;  
        Statement sta = null;  
        ResultSet rs = null;  
        try {  
            PhoenixDB pDB = new PhoenixDB();
        	conn = pDB.getConn();
        	sta = conn.createStatement();  
            rs = sta.executeQuery("select * from tb");  
            ResultSetMetaData md = rs.getMetaData(); //获得结果集结构信息,元数据  
            int columnCount = md.getColumnCount();   //获得列数   
            while (rs.next()) {  
                List<Object> l = new ArrayList<Object>();  
                for (int i = 1; i <= columnCount; i++) {
                	l.add(rs.getObject(i));
                }  
                list.add(l);  
      
            }  
        }  catch (SQLException e) {  
            e.printStackTrace();  
        }  
        return "success";  
    }