java实现下载文件demo java实现下载模板

前端js

function downloadFile(){ var url=contextPath + 'downloadFile/downModel?fileName='模板的名称'.xls'; window.open(url);//跳转后台的路径 }

这就是后台完整的下载模板的代码

@ApiOperation("下载模板")
@RequestMapping(value = "/downModel",method = RequestMethod.GET,produces="application/json")
public Result<Object> downModel(HttpServletResponse response, HttpServletRequest request) {
    Result<Object> result=Result.ok();
    String fileName = request.getParameter("fileName");
    ServletOutputStream out;
    response.setContentType("multipart/form-data");
    response.setCharacterEncoding("UTF-8");
    response.setContentType("text/html");
    try{
        String filePath = getClass().getResource("/static/template/" + fileName).getPath();//文件在项目中的存放路径
        String userAgent = request.getHeader("User-Agent");
        if (userAgent.contains("MSIE") || userAgent.contains("Trident")) {
            fileName = URLEncoder.encode(fileName, "UTF-8");
        } else {
            // 非IE浏览器的处理：
            fileName = new String((fileName).getBytes("UTF-8"), "ISO-8859-1");
        }
        filePath = URLDecoder.decode(filePath, "UTF-8");
        response.setHeader("Content-Disposition", "attachment;fileName=" + fileName);
        FileInputStream inputStream = new FileInputStream(filePath);
        out = response.getOutputStream();
        int b = 0;
        byte[] buffer = new byte[1024];
        while ((b = inputStream.read(buffer)) != -1) {
            // 4.写到输出流(out)中
            out.write(buffer, 0, b);
        }
        inputStream.close();

        if (out != null) {
            out.flush();
            out.close();
        }
    }catch (Exception e){
        log.error(ExceptionUtils.getMessage(e));
        log.error(ExceptionUtils.getStackTrace(e));
        return Result.error(e.getMessage());
    }
    return null;
}