java.io.FileNotFoundException: XXX.jpg(系统找不到指定的文件。)怎么解决

public class FileUploadServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private String uploadPath = "D:\\temp\\";//上传文件的目录
    private String tempPath = "D:\\temp\\buffer";//临时文件目录
    File tempPathFile;
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
super.doGet(req, resp);
this.doPost(req, resp);
}
    @SuppressWarnings("unchecked")
public void doPost(HttpServletRequest request, HttpServletResponse response)
           throws IOException, ServletException {
request.setCharacterEncoding("gbk");
String action = request.getParameter("action");
if(action == null){//当action为空时
request.getRequestDispatcher("error.jsp").forward(request,response);
return;
}
if(action.equals("insertHeadImage")){//上传头像动作
String tdis = request.getParameter("tdis");
if(tdis == null){
tdis = "";
}
     HttpSession session=request.getSession(true);
String uid = (String) session.getAttribute("uid");
     try {
     //实例化一个硬盘文件工厂,用来配置上传组件ServletFileUpload
     DiskFileItemFactory factory = new DiskFileItemFactory();
     factory.setSizeThreshold(4096);//设置缓冲区大小，这里是4kb
     factory.setRepository(tempPathFile);//设置缓冲区目录

     //用以上工厂实例化上传组件
     ServletFileUpload upload = new ServletFileUpload(factory);

     upload.setSizeMax(3*1024*1024);//设置最大文件尺寸，这里是3MB

     List fileitems = upload.parseRequest(request);//得到所有的文件
     Iterator i = fileitems.iterator();
     while (i.hasNext()) {
     FileItem fi = (FileItem) i.next();
     String fileName = fi.getName();
     if (fileName != null){
     if(!fileName.equals(""))
     {
     File fullFile = new File(fi.getName());
     DBUtil.insertDCMS_head(tdis, fullFile, Integer.parseInt(uid));//存储到数据库
     //File savedFile = new File(uploadPath, fullFile.getName());
                   //fi.write(savedFile);
     }
     }
     }
     request.getRequestDispatcher("changeHead.jsp").forward(request,response);
     } catch (Exception e) {//可以跳转出错页面
     e.printStackTrace();//打印异常信息
     request.getRequestDispatcher("error.jsp").forward(request,response);
     }
} --------------------编程问答-------------------- 补充：
String fileName = fi.getName();
得到的是文件名还是具体路径 --------------------编程问答-------------------- getName(); 得到的是文件名

补充：Java ,  非技术区