hibernate多表查询问题!摆脱了!
程序运行后报错  
javax.servlet.ServletException:   Invalid   path:    'null.buy_info_id '   [from   fd.mmk.zhangjian.hibernatePogo.Mmk_information_buy_info,fd.mmk.zhangjian.hibernatePogo.Mmk_information_compete_info   where   Mmk_information_compete_info.buy_info_id   =   Mmk_information_buy_info.id   and   Mmk_information_buy_info.user_id   =   ?] 
 	org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:523) 
 	org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:421) 
 	org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:224) 
 	org.apache.struts.action.ActionServlet.process(ActionServlet.java:1194) 
 	org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) 
 	javax.servlet.http.HttpServlet.service(HttpServlet.java:690) 
 	javax.servlet.http.HttpServlet.service(HttpServlet.java:803) 
------解决方案--------------------对象.属性   这样用有问题 先用as 然后引用才行
------解决方案--------------------把你的 HQL 帖出来
------解决方案--------------------应该是语句拼装错了吧
------解决方案--------------------from  
fd.mmk.zhangjian.hibernatePogo.Mmk_information_buy_info,
fd.mmk.zhangjian.hibernatePogo.Mmk_information_compete_info  
where  
Mmk_information_compete_info.buy_info_id   =   Mmk_information_buy_info.id  
and  
Mmk_information_buy_info.user_id   =   ?
==================================================
(@!#……¥(@#&)¥&!)×¥!——
有你这么些的吗?
http://blog.csdn.net/cmtobby/archive/2007/08/22/1754994.aspx
自己好好去看下。。。
------解决方案--------------------where   Mmk_information_compete_info.buy_info_id   =   Mmk_information_buy_info.id   and   Mmk_information_buy_info.user_id   =   ?]  
这句HQL有问题,你要么"="号后全部跟变量,要么都用?号