public ArrayList<User> select(String sql){            
        ArrayList<User> list = new ArrayList<User>();
        Connection conn = null;
        Statement stmt = null;
        ResultSet rs = null;
        try {
            conn = getConnection();
            stmt = conn.createStatement();
            rs = stmt.executeQuery(sql);
            while(rs.next()){                       //将rs结果集中的每一条记录都转化成User对象,再放进list中
                User user = new User();    
                user.setTel(rs.getString("tel"));
                user.setUsername(rs.getString("username"));
                user.setAddr(rs.getString("addr"));
                user.setMail(rs.getString("mail"));
                user.setType(rs.getInt("type"));
                user.setYf(rs.getDouble("yf"));
                user.setNum(rs.getInt("num"));
                user.setYb(rs.getInt("yb"));
                user.setFp(rs.getInt("fp"));    
                user.setPrice(rs.getDouble("price"));
                user.setNum(rs.getInt("num"));
                user.setId(rs.getString("id"));                        
                user.setFk(rs.getInt("fk"));
    
                list.add(user);
            }
        } catch (SQLException e) {
            System.out.println("Sql异常1");
        }
        finally{
            if(rs!=null){
                try {
                    rs.close();
                } catch (SQLException e) {
                    System.out.println("关闭rs时异常");
                }
            }
            if(stmt!=null){
                try {
                    stmt.close();
                } catch (SQLException e) {
                    System.out.println("关闭stmt时异常");
                }
            }
            if(conn!=null){
                try {
                    conn.close();
                } catch (SQLException e) {
                    System.out.println("关闭conn时异常");
                }
            }
        }
        return list;
    }

<%   
         
         UsersDAO db = new UsersDAO();
         String sql="select *from ZTC";
         ArrayList<User> list = db.select(sql); 
         if(list.isEmpty()==false)
         {
            for(int i=0;i<list.size();i++)
           
             {
                 User user = list.get(i);
      %>
                 <tr>
                 <td><%=user.getId()%></td>
                 <td><%=user.getUsername()%></td>
                 <td><%=user.getTel()%></td>
                 <td><%=user.getAddr()%></td>
                 <td><%=user.getMail()%></td>
                 <td><%=user.getType()%></td>  
                 <td><%=user.getNum()%></td>
                 <td><%=user.getYb()%></td>
                 <td><%=user.getYf()%></td>
                 <td><%=user.getFp()%></td>
                 <td><%=user.getPrice()%></td>  
                 <td><%=user.getFk()%></td>        
                 <td>