Spring MVC - 两种文件下载方式

第一种、比较优雅，实际应用时遇到问题：IE8下载Excel，内容乱码（待解决）

解决方法：1、使用英文文件名。

                     2、硬编码文件名。String fileName = "我是文件名.xls";

     3、偶尔正常，崩溃了。2015.7.3：硬编码方式也不行了，改用了第二种方法正常。

@RequestMapping(value = "/download/{fileName}")
public ResponseEntity<byte[]> downloadFile(@PathVariable String fileName)
throws Exception {
fileName = fileName + ".xls";
// 1.拼接真实路径
String realPath = getRequest().getServletContext().getRealPath("/") + "/" + fileName;
// 2.读取文件
File file = new File(realPath);

// 4.设置格式
HttpHeaders headers = new HttpHeaders();
headers.setContentDispositionFormData("attachment", encodeChineseDownloadFileName(getRequest(), fileName));
headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
// 5.返回下载
return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),
headers, HttpStatus.OK);
}

/**
 * Description: 根据不同浏览器处理中文字符
 * @param request
 * @param fileName
 * @return
 * @throws UnsupportedEncodingException
 */
private String encodeChineseDownloadFileName(HttpServletRequest request, String fileName)
throws UnsupportedEncodingException{
String resultFileName = "";
String agent = request.getHeader("User-Agent").toUpperCase();
if(null == agent){
resultFileName = fileName;
}else{
if(agent.indexOf("FIREFOX") != -1 || agent.indexOf("CHROME") != -1){  //firefox, chrome
resultFileName = new String(fileName.getBytes("UTF-8"), "iso-8859-1");
}else{  //ie7+
resultFileName =  URLEncoder.encode(fileName, "UTF-8");
resultFileName = StringUtils.replace(resultFileName, "+", "%20");  //替换空格
}
}
return resultFileName;
}

第二种、不会出现上面所说的情况

@RequestMapping(value = "/download/{fileName}")
public void downloadFile(@PathVariable String fileName) throws IOException{
// 拼接真实路径
String realPath = getRequest().getServletContext().getRealPath("/")
+ "/" + fileName + ".xls";
// 读取文件
File file = new File(realPath);
if(file.exists()){
OutputStream os = new BufferedOutputStream(getResponse().getOutputStream());
try {
getResponse().setContentType("application/octet-stream");
if (getRequest().getHeader("User-Agent").toUpperCase().indexOf("MSIE") > 0) {   //IE浏览器
fileName = URLEncoder.encode(fileName + ".xls", "UTF-8");  
} else {  
fileName = URLDecoder.decode(fileName + ".xls");//其他浏览器
}

getResponse().setHeader("Content-disposition", "attachment; filename="
+ new String(fileName.getBytes("utf-8"), "ISO8859-1")); // 指定下载的文件名
os.write(FileUtils.readFileToByteArray(file));
os.flush();
} catch (IOException e) {
e.printStackTrace();
} finally {
if(os != null){
os.close();
}
}
}
}