大家帮忙看看这oracle代码错在哪里?
public ArrayList<Product> hclassselect(int currpage,int count)
  {  
  ArrayList<Product> list=new ArrayList<Product>();
  Connection conn=BaseDao.getConn();
  PreparedStatement ps=null;
  ResultSet rs=null;
  Product p=null;
  try {
  ps = conn.prepareStatement("select * from (select epc_name,epc_class_id,et_type,et_id"+  
  "from (select a.epc_name,a.epc_id,b.* from easybuy_pclass a,easybuy_ptype b" +
  " where a.epc_class_id=b.epc_class_id order by b.et_id))" +
  "where et_id between"+((currpage-1)*count+1)+"and"+currpage*count); 
  rs = ps.executeQuery();
  while(rs.next())
  {
  p=new Product();
  p.setFid(rs.getInt("epc_class_id"));
  p.setFname(rs.getString("epc_name"));
  p.setSid(rs.getInt("et_id"));
  p.setSname(rs.getString("et_name"));
  list.add(p);
  }

} catch (Exception e) {
e.printStackTrace();
}
finally
{
BaseDao.closeAll(rs, ps, conn);
}
  return list;
  }

  rs总是为null怎么搞的

------解决方案--------------------
是不是报异常了，还有你拼的语句是不是少了空格了，造成异常了
------解决方案--------------------

Java code

 "where et_id between"+((currpage-1)*count+1)+"and"+currpage*count);