注册用户代码有何错误(这个帖子的给分将在真是很奇怪？？？里给出)

Question

op_user.java
package bookshop.run;import java.sql.*;
import java.util.Vector;
import javax.servlet.http.HttpServletRequest;
import bookshop.util.*;
import bookshop.book.*;public class op_user extends DataBase{
        private user user = new user();                                //新的用户对象
        private javax.servlet.http.HttpServletRequest request;  //建立页面请求
        private Vector userlist;                        //显示用户列表向量数组
        private int page = 1;                                        //显示的页码
        private int pageSize=8;                                        //每页显示的图书数
        private int pageCount =0;                                //页面总数
        private long recordCount =0;                                //查询的记录总数
        private String message = "";                                //出错信息提示
        private String username = "";                              //注册后返回的用户名
        private long userid = 0;                             //注册后返回的用户ID  public op_user() {
  }
  //添加新用户
  public boolean add(HttpServletRequest req) throws Exception {
        if (getRequest(req)) {
            DataBase db = new DataBase();
            db.connect();
            stmt = db.conn.createStatement ();
            sqlStr = "select * from shop_user where username = '" +
                      user.getUserName() +"'";
            sqlStr = "insert into shop_user (username,password,Name,Sex,"+
                     "Address,Phone,Post,Email,RegTime,RegIpaddress) values ('";
            sqlStr = sqlStr + dataFormat.toSql(user.getUserName()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getPassWord()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getNames()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getSex()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getAddress()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getPhone()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getPost()) + "','";
            sqlStr = sqlStr + dataFormat.toSql(user.getEmail()) + "',now(),'";
            sqlStr = sqlStr + user.getRegIpAddress() + "')";
            try{
                stmt.executeUpdate(sqlStr);
                sqlStr = "select max(id) from shop_user where username = '" +
                         user.getUserName()+ "'";
                         rs = stmt.executeQuery(sqlStr);
                         while (rs.next()){
                              userid = rs.getLong(1);
                              }
                             rs.close();
                             return true;
                }catch (Exception sqle){
                  System.out.print(sqle.getMessage());
                  return false;
                }
           } else{
            return false;
           }  }
  //分析页面转递的参数
  public boolean getRequest(javax.servlet.http.HttpServletRequest newrequest) {
       boolean flag = false;
       try {
        request = newrequest;
        String ID = request.getParameter("userid");
        if (ID!=null ){
        userid = 0;
        try{
            userid = Long.parseLong(ID);
            user.setId(userid);
            }catch (Exception e){
                 message = message + "你要修改的用户号出错！";
            }
         }         username = request.getParameter("username");
         if (username==null || username.equals("")){
              username = "";
              message = message + "用户名为空!";
              }
              user.setUserName(getGbk(username));
              String password = request.getParameter("passwd");
              if (password==null || password.equals("")){
                  password = "";
                  message = message + "密码为空!";
                  }
              String pwdconfirm = request.getParameter("passconfirm");
              if (!password.equals(pwdconfirm)){
                 message = message + "确认密码不相同!";
                 }
              user.setPassWord(getGbk(password));
              String names = request.getParameter("names");;
              if (names==null){
                   names = "";
                   }
              user.setNames(getGbk(names));
              String sex = request.getParameter("sex");
              user.setSex(getGbk(sex));
              String address = request.getParameter("address");
              if (address == null){
                   address = "";
                  }
              user.setAddress(getGbk(address));
              String post = request.getParameter("post");
              if (post == null){
                  post = "";
                 }
               user.setPost(getGbk(post));
              String phone = request.getParameter("phone");
              if (phone== null){
                  phone = "";
              }
             user.setPhone(phone);
             String email = request.getParameter("email");
             if (email == null){
                  email = "";
                  }
              user.setEmail(getGbk(email));
             String IP = request.getRemoteAddr();
             user.setRegIpAddress(IP);
             if (message.equals("")){
                  flag = true;
                  }
               return flag;
        }catch (Exception e){
            return flag;
            }
}
  public String getGbk( String str) {
               try  {
                return new String(str.getBytes("ISO8859-1"));
                }catch (Exception e){
                  return str;
                  }
          }
  public int getPage() {                                //显示的页码
                              return page;
                      }
                      public void setPage(int newpage) {
                              page = newpage;
                      }                      public int getPageSize(){                        //每页显示的图书数
                              return pageSize;
                      }
                      public void setPageSize(int newpsize) {
                              pageSize = newpsize;
                      }                      public int getPageCount() {                //页面总数
                              return pageCount;
                      }
                      public void setPageCount(int newpcount) {
                              pageCount = newpcount;
                      }                      public long getRecordCount() {
                              return recordCount;
                      }
                      public void setRecordCount(long newrcount) {
                              recordCount= newrcount;
                      }                      public String getMessage() {
                              return message;
                      }                      public void setMessage(String msg) {
                              message = msg;
                      }                      public void setUserid(long uid) {
                              userid = uid;
                      }
                      public long getUserid() {
                              return userid;
                      }                      public void setUserName(String uName) {
                              username = uName;
                      }                      public String getUserName() {
                              return username;
                      }
                      public Vector getUserlist() {
                           return userlist;
                       }};