修改传来ID的用户信息

<%//接收要修改的用户ID
  long id;
try{
  id=Long.parseLong(request.getParameter("id"));
   }catch (Exception e)
   {
    id=0;
   }
  %>
  <%//接收用户提交的数据
  String username=codeToString(request.getParameter("username"));
if(username==null){
    username="";
    }

String name=codeToString(request.getParameter("name"));
   if(name==null){
    name="";
    }
String age=codeToString(request.getParameter("age"));
  int ageint;
  try{
    ageint=Integer.parseInt(age.trim());
  }catch (Exception e)
  {
   ageint=0;//没有输入年龄的，则默认为0；
  }
  String sex=codeToString(request.getParameter("sex"));
   if(sex==null){
    sex="";
    }
  String address=codeToString(request.getParameter("address"));
   if(address==null){
    address="";
    }
  String tel=codeToString(request.getParameter("tel"));
   if(tel==null){
    tel="";
    }
   
  %>
  <%//构造要修改的SQL语句
  String sqlString=null;
  sqlString="update usertable set username='"+username+"',name='"+name+"',age="+ageint+",sex='"+sex+"',address='"+address+"',tel='"+tel+"'"+"where id="+id ;
  %>
  <%//执行sql语句
   try{
     Connection con;
     Statement sql;
     Class.forName("com.mysql.jdbc.Driver");
     con=DriverManager.getConnection("jdbc:mysql://localhost:3306/jsp","root","7056503");
     sql=con.createStatement();
     sql.executeUpdate(sqlString);
     con.close();
   }catch(Exception e1){
    out.print(" SQL异常！");
   }
   %>