Java 读取类路径下的文件 返回给浏览器

@RequestMapping("/downloadTemplate")
	public byte[] downloadTemplate(HttpServletRequest request,HttpServletResponse response){
		
        String fileName = "Budget_Template.xlsx";  
        response.setContentType("application/vnd.ms-excel");  
        response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\"");  
        OutputStream out;
		try {
			out = response.getOutputStream();
			URL base = this.getClass().getResource(""); //先获得本类的所在位置，如/home/popeye/testjava/build/classes/net/
	        String path = new File(base.getFile(), "/template.xlsx").getCanonicalPath();
	        
			byte[] buf = new byte[1024];
			InputStream in = new FileInputStream(new File(path));  
			int tempbyte;
            while ((tempbyte = in.read(buf)) != -1) {
                out.write(buf);
            }
            out.flush();
            out.close();
		} catch (IOException e1) {
			e1.printStackTrace();
		}
		return null;

	}