请教bean调用时出错！？？

[shongshan]

useBean：
package jbean;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpServletRequest;
public class usession{
public String getSe(){
HttpServletRequest req=null;
HttpSession session=req.getSession(true);
return (String)session.getAttribute("useranme");
}
}

jsp:
<jsp:useBean id="uSession" scope="page" class="jbean.usession"/>
<%
session.setAttribute("username","xian");
out.println(uSession.getSe()+"<br>");
%>

[shongshan]

下面是出错：

org.apache.jasper.JasperException
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:358)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


root cause

java.lang.NullPointerException
jbean.usession.setSe(usession.java:7)
org.apache.jsp.javabean_jsp._jspService(javabean_jsp.java:142)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:133)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:311)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:301)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:248)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856

[mysam]

把出错代码贴上来