Servlet下载文件代码

public class FileServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        String realPath = "F:\\ideaSpace\\New\\servletDemo\\src\\main\\resources\\1.png";
        System.out.println("下载文件的路径："+realPath);
        String fileName = realPath.substring(realPath.lastIndexOf("\\")+1);
        //F:\ideaSpace\New\servletDemo\src\main\resources\1.png
        resp.setHeader("Content-Disposition","attachement;filename="+fileName);
        FileInputStream in = new FileInputStream(realPath);
        int len = 0;
        byte[] buffer = new byte[1024];
        ServletOutputStream out = resp.getOutputStream();
        while((len=in.read(buffer))>0){
            out.write(buffer,0,len);
        }
        in.close();
        out.close();
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        super.doPost(req, resp);
    }
}