javax.servlet.ServletException: [Ljava.lang.Object;

来源：互联网发布：北京音像大厦知乎编辑：程序博客网时间：2024/05/16 11:42

HTTP Status 500 -

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;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.doPost(ActionServlet.java:432)javax.servlet.http.HttpServlet.service(HttpServlet.java:709)javax.servlet.http.HttpServlet.service(HttpServlet.java:802)com.zq.utils.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:24)

root cause

java.lang.ClassCastException: [Ljava.lang.Object;com.zq.struts.user.action.UserAction.userLogin(UserAction.java:403)com.zq.struts.user.action.UserAction.doExecute(UserAction.java:118)com.zq.struts.action.BaseAction.execute(BaseAction.java:98)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.doPost(ActionServlet.java:432)javax.servlet.http.HttpServlet.service(HttpServlet.java:709)javax.servlet.http.HttpServlet.service(HttpServlet.java:802)com.zq.utils.SetCharacterEncodingFilter.doFilter(SetCharacterEncodingFilter.java:24)

note The full stack trace of the root cause is available in the Apache Tomcat/5.0.28 logs.

一下内容摘自互联网（转）

String sql = "select {P.*} from Personreg P where P.name = :name and P.password = :password";
以上Query的list()方法返回的集合中存放的是对象数组的元素，这个对象数组中才是存放了Personreg对象。
应该if (iterator.hasNext()){
                Object[] row = (Object[])iterator.next();
                Personreg personreg = (Personreg)row[0];
                System.out.println(personreg.getId());
        }

另外String hql = "from Personreg P where P.name = :name and P.password = :password"，这里，因为你语句中用了别名.属性名，所以前面一定要指定别名，否则语法错误; 或者不指定别名的前况下直接指定属性名就好，可以用String hql = "from Personreg where name = :name and password = :password"。