***大家看看,怎么会出这个问题,List的数据不能强制转换,报错误!***

[zslearning]

其中用到MyEclipse的Hibernate框架

public class XiangmuDAO extends HibernateDaoSupport{
......................
....................

public List findByStr(String queryString, Object[] value) {
log.debug("finding Xiangmu by String sql: ");
try {

return getHibernateTemplate().find(queryString, value);//是不是这句有问题
} catch (RuntimeException re) {
log.error("find by property name failed", re);
throw re;
}
}
}

在另一个程序中调用:

String queryString = "from Xiangmu m,User u where m.type=? and m.department=u.department and u.department=?";
String[] m_param =new String[2];
m_param[0] = "123";
m_param[1] = m_department;

List spList = xmdao.findByStr(queryString, m_param);//得到项目列表
Xiangmu xm = (Xiangmu)spList.get(0);//****注意:此处提示出错?为什么

这是浏览器的提示:javax.servlet.ServletException: [Ljava.lang.Object; cannot be cast to com.zs.db.Xiangmu

请指点?
怎样更正这个错误!!!!!

[xiaoxiao0714]

是不是持久层框架里返回的变量格式不是“Xiangmu”？

[li_d_s]

queryString的值是啥？

[hllwuxin]

spList.get(0);//在哪，，我怎么找不到，

最好给个完整点的，这样怎么找啊

[zslearning]

List spList = xmdao.findByName("czj");//这样就好使,
但下面这面就不行
String queryString = "from Xiangmu m,User u where m.type=? and m.department=u.department and u.department=?";
String[] m_param =new String[2];
m_param[0] = "123";
m_param[1] = m_department;

List spList = xmdao.findByStr(queryString, m_param);//

而且
Iterator it= spList.iterator();
while(it.hasNext())
{
Xiangmu xm= (Xiangmu)it.next();//这样的话也强制转换不了
}


出这种问题的可能性?可能哪里有错误!!

[zuguanqun]

Xiangmu 这个对象和你 queryString = "from Xiangmu m,User u where m.type=? and m.department=u.department and u.department=?"这个sql查出来的对象不一致

[zslearning]

异常信息如下:
type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: [Ljava.lang.Object; cannot be cast to com.zs.db.Xiangmu
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:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
com.zs.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:123)


root cause

java.lang.ClassCastException: [Ljava.lang.Object; cannot be cast to com.zs.db.Xiangmu
com.zs.struts.action.GetXiangmuAction.execute(GetXiangmuAction.java:74)
org.springframework.web.struts.DelegatingActionProxy.execute(DelegatingActionProxy.java:106)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:419)
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:689)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
com.zs.filters.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:123)


note The full stack trace of the root cause is available in the Apache Tomcat/5.5.20 logs.

[zslearning]

Xiangmu 这个对象和你 queryString = "from Xiangmu m,User u where m.type=? and m.department=u.department and u.department=?"这个sql查出来的对象不一致


确实是这里有问题,谢谢了