Spring MVC做文件下載功能時，遇到了文件名編碼問題。經過百度，參考了以下兩篇文章，解決了編碼問題。

http://www.iefans.net/xiazai-wenjian-http-bianma-content-disposition/

https://yq.aliyun.com/articles/38945

最終代碼如下：

    public ResponseEntity<InputStreamResource> downloadFile(Path filePath) 
            throws FileNotFoundException {
        File file 
 
= filePath.toFile();
        
        String mimeType = URLConnection.guessContentTypeFromName(file.getName());
        if (mimeType == null) {
            mimeType = MediaType.APPLICATION_OCTET_STREAM_VALUE;
        }
        
        HttpHeaders respHeaders = new HttpHeaders();
        respHeaders.set(HttpHeaders.CONTENT_TYPE, mimeType);
        respHeaders.setContentLength(file.length());
        String encodedFileName 
 
= file.getName();
        try {
            encodedFileName = URLEncoder.encode(encodedFileName, "UTF-8");
        } catch (UnsupportedEncodingException e) {
            logger.error("文件名編碼錯誤！", e);
        }
        respHeaders.set(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=\"" + encodedFileName + "\""
                + "; filename*=UTF-8‘‘" +
 
 encodedFileName);
        
        InputStreamResource isr = new InputStreamResource(new FileInputStream(file));
        return new ResponseEntity<InputStreamResource>(isr, respHeaders, HttpStatus.OK);
    }

先對原始文件名按UTF-8編碼，再設置Content-Disposition。Content-Disposition中設置了兩次filename，是為了兼容更多瀏覽器。

Spring MVC文件下載的文件名編碼問題