我做一个jsp登录页，但不知什么原因出错，高手给条明路
代码如下：
<%
           String user=new String(request.getParameter("user").getBytes("ISO-8859-1"));
           String pass=new String(request.getParameter("pass").getBytes("ISO-8859-1"));
          
           Connection conn;
           Statement sql;
           ResultSet rs;
           try
           {
              Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
           }
           catch(ClassNotFoundException e){}
           try
           {
              conn=DriverManager.getConnection("jdbc:odbc:aa","","");
              sql=conn.createStatement();
              rs=sql.executeQuery("SELECT * FORM username WHERE username="+user+"password="+pass);
              if(rs.next())
              {
                 if(user.equals("user")&&pass.equals("password"))
                 {
                    response.sendRedirect("index.jsp");
                 }
                else
                    {
                       out.print("您的密码或者用户名有误，请从新登录");
                    }      
              }
             conn.close();
             }
            catch(SQLException e1){}
      %>