<%@ page language="java" pageEncoding="gb2312"%>
<%@ page import="java.util.List"%>
<%@ page import="com.ssh.myshop.bean.GoodsType"%>
<jsp:useBean id="goodsTypeDaoImpl" class="com.ssh.myshop.dao.impl.GoodsTypeDaoImpl" scope="session" >
</jsp:useBean>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>商品添加</title>
</head>
<body>
<%
List<GoodsType> list=goodsTypeDaoImpl.selectList();
%>
</body>
</html>这是一个jsp页面....下面是GoodsTypeDaoImpl中的selectList()方法 属性都已经注入,在别的地方这个方法是没有问题的@SuppressWarnings("unchecked")
public List<GoodsType> selectList() {
// TODO Auto-generated method stub
String hql="from GoodsType";
return (List<GoodsType>)this.getHibernateTemplate().find(hql);
}就这样的代码...我想测一下有没写错..就访问了一下这个jsp页面 没想到老出现这样的错误
org.apache.jasper.JasperException: An exception occurred processing JSP page /addGoodsName.jsp at line 1411: </head>
12: <body>
13: <%
14: List<GoodsType> list=goodsTypeDaoImpl.selectList();
15: %>
16: </body>
17: </html>
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:505)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:416)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:413)
root cause java.lang.NullPointerException
com.ssh.myshop.dao.impl.GoodsTypeDaoImpl.selectList(GoodsTypeDaoImpl.java:31)
org.apache.jsp.addGoodsName_jsp._jspService(addGoodsName_jsp.java:78)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:374)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:342)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:267)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:413)实在是想不明白为什么会出现这样的问题
确定不为空?,设个断点跟踪进去看看。另外return前,先用个变量代替,然后看那个变量里面的值