window.location调用java方法时出现 The requested resource is not available.

JSP代码
<%@ page language="java" import="jikon.action.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">



Test
<br> window.location = &quot;headTitleAction!list.action&quot;;<br><br> //window.location =;<br><br>




java代码：
@Action("headTitleAction")
@Namespace("/")
@Results({
@Result(name="success",location="/WEB-INF/file/listTrefer.jsp"),
@Result(name="img",location="/WEB-INF/file/uploadimg.jsp")
})
public class HeadTitleAction {

public String list() {

    headTitleList =  headTitleService.find();

    for(int i=0;i<headTitleList.size();i++) {

·····
这个问题可能是什么原因造成的，怎么解决？