类得不到this.username的值

Question

类文件如下
package user;
import java.sql.*;
import common.DBConn;
public class SupplyTypeList {
  private String username;
  private String title;
  private int id;
  public SupplyTypeList(){}
  public void setUserid(int m)
  {
  this.userid=m;
  } 
  public void setUsername(String name)
  {
  this.username=name;
  } //会员供应信息分类
  public StringBuffer getBuffer(){
  StringBuffer buffer=new StringBuffer();
  try{
  DBConn conn=new DBConn();
  String sql="SELECT * FROM supplytype WHERE userid="+userid+" ORDER BY sequence"; 
    ResultSet rs = conn.query(sql);
  while(rs.next())
  {
  id=rs.getInt(1);
  title=rs.getString("title");
  buffer.append("<li>·<a href='/shop/supplytype"+id+"/"+username+".html'>");
  buffer.append(title);
  buffer.append("</a></li>\r\n");
  }  
   conn.DBclose();
  }
  catch(Exception e){
    System.out.print(e.toString());
  }
  return buffer;
}
}JSP文件如下
           <jsp:useBean id="supplytype" scope="page" class="user.SupplyTypeList" />
           <jsp:setProperty name="supplytype" property="userid" value="111" />
           <jsp:setProperty name="supplytype" property="username" value="555" />
           <jsp:getProperty name="supplytype" property="buffer" />userid 111这个值能得到，但是username 555这个值得不到，是null什么原因呢
显示的结果是/shop/supplytype111/null.html
我想得到的结果是/shop/supplytype111/555.html

Answer 1

1.private int id; 还是 private int userid;  ?
2.title=rs.getString("title");后增加username=rs.getString("username");
3.<jsp:setProperty name="supplytype" property="username" value="555" /> 去掉