javaweb 文件名下载乱码问题终极解决方案

之前看很多博客都是通过 判断userAgent来处理文件名的中文乱码问题，如下

 if (userAgent.indexOf("MSIE")!=-1 || userAgent.indexOf("Trident")!=-1 || userAgent.indexOf("Edge")!=-1 ) {     // ie     fileName = new String(fileName.getBytes("GBK"), "iso-8859-1");                     } else if (null != userAgent && -1 != userAgent.indexOf("Mozilla")) {           // 火狐,chrome等                         fileName = new String(fileName.getBytes("UTF-8"), "iso-8859-1");                     } 

但博主实际开发中发现，这种也不是百分之百有效，最简单粗暴的方式就是把fileName 先BASE64编码存为url，然后下载时候再把fileName用BASE64解码，就可以规避浏览器对中文编码不一致的问题了，代码如下：

package com.nercel.cyberhouse.ws.sns;import java.io.BufferedInputStream;import java.io.BufferedOutputStream;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.text.SimpleDateFormat;import java.util.Date;import java.util.UUID;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.bind.annotation.ResponseBody;import org.springframework.web.multipart.MultipartFile;import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder;import com.alibaba.fastjson.JSON;import com.nercel.cyberhouse.util.ServerConfig;import com.nercel.cyberhouse.vo.UFile;import com.nercel.cyberhouse.vo.UploadFile;import java.util.regex.*; @Controller@RequestMapping("sns")public class FileUpload {    private String CYBERHOUSE_PATH =  ServerConfig.get("cyberhouse.root");       @RequestMapping(value = "/uploadFile", produces = "text/plain; charset=utf-8")       public @ResponseBody String uploadFile(@RequestParam(value = "file", required = false) MultipartFile file,int userId,HttpServletRequest request, HttpServletResponse response) {              UploadFile upFile = new UploadFile();            String path = request.getSession().getServletContext().getRealPath("upload/sns/"+userId+"/");            //  String fileName = StringFilter(file.getOriginalFilename());            String fileName = file.getOriginalFilename();            String ext=fileName.substring(fileName.lastIndexOf(".")+1);            if(file.getSize()>1024*1024*50){                upFile.setCode(1);                upFile.setMsg("单个文件/图片大小不能超过50M!");                return JSON.toJSONString(upFile);            }            String name=UUID.randomUUID().toString()+"."+ext;            String downLoadPath=path+"/"+name;            File targetFile = new File(path,name);              if(!targetFile.exists()){                  targetFile.mkdirs();              }             try {                file.transferTo(targetFile);                upFile.setCode(0);              UFile uf=new UFile();              uf.setName(fileName);              byte[] b = null;                b = fileName.getBytes("utf-8");                uf.setSrc(CYBERHOUSE_PATH+"/sns/downLoadFile?downLoadPath="+downLoadPath+"&fileName="+new BASE64Encoder().encode(b));              upFile.setData(uf);            } catch (Exception e) {                  e.printStackTrace();              }              return JSON.toJSONString(upFile);          }        @RequestMapping("/downLoadFile")          public void downLoadFile(String downLoadPath, String fileName,HttpServletResponse response,HttpServletRequest request) throws UnsupportedEncodingException {               BufferedInputStream bis = null;                  BufferedOutputStream bos = null;                          byte[] b = null;                  String resultFileName = null;                      BASE64Decoder decoder = new BASE64Decoder();                          try {                            b = decoder.decodeBuffer(fileName);                        } catch (IOException e1) {                            e1.printStackTrace();                        }                          resultFileName = new String(b, "utf-8");                  try {                      response.setCharacterEncoding("UTF-8");                     long fileLength = new File(downLoadPath).length();                    String userAgent = request.getHeader("User-Agent");                                    response.setHeader("Content-disposition", "attachment; filename="+new String(resultFileName.getBytes("gbk"),"iso-8859-1"));                    response.setContentType("application/x-download;");                    response.setHeader("Content-Length", String.valueOf(fileLength));                      bis = new BufferedInputStream(new FileInputStream(downLoadPath));                      bos = new BufferedOutputStream(response.getOutputStream());                      byte[] buff = new byte[2048];                      int bytesRead;                      while (-1 != (bytesRead = bis.read(buff, 0, buff.length))) {                          bos.write(buff, 0, bytesRead);                      }                      bos.flush();                  } catch (Exception e) {                  } finally {                      if (bis != null) {                          try {                            bis.close();                        } catch (IOException e) {                            e.printStackTrace();                        }                    }                      if (bos != null) {                          try {                            bos.close();                        } catch (IOException e) {                            e.printStackTrace();                        }                      }                  }          }         // 过滤特殊字符         public static String StringFilter(String str) throws PatternSyntaxException{                   // 清除掉所有特殊字符和空格              String regEx="[`~!@#$%^&*()+=|{}':;',\\[\\]<>/?~！@#￥%……&*（）——+|{}【】‘；：”“’。，、？ ]";                Pattern p = Pattern.compile(regEx);                   Matcher m = p.matcher(str);                   return m.replaceAll("").trim();            }       //layui上传文件公共服务       @RequestMapping(value = "/upload", produces = "text/plain; charset=utf-8")       public @ResponseBody String upload(@RequestParam(value = "file", required = false) MultipartFile file,HttpServletRequest request, HttpServletResponse response) {              UploadFile upFile = new UploadFile();            String msg="上传失败！";            long fileSize = file.getSize();            System.out.println("fileSize="+fileSize);            if(fileSize>2097152){                upFile.setCode(1);                upFile.setMsg("上传文件不能超过2M！");                return JSON.toJSONString(upFile);               }            String fileName = StringFilter(file.getOriginalFilename());            String fileType= fileName.substring(fileName.lastIndexOf(".")+1);            Date now = new Date();             SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd");//可以方便地修改日期格式            String today = dateFormat.format(now);             String path = request.getSession().getServletContext().getRealPath("upload/layuiUploads/"+fileType+"/"+today);            String name=UUID.randomUUID().toString()+fileName;            String downLoadPath=path+"/"+name;            File targetFile = new File(path,name);              if(!targetFile.exists()){                  targetFile.mkdirs();              }             try {                file.transferTo(targetFile);              upFile.setCode(0);              UFile uf=new UFile();              uf.setName(fileName);              uf.setSrc(CYBERHOUSE_PATH+"/sns/downLoadFile?downLoadPath="+downLoadPath+"&fileName="+fileName);              upFile.setData(uf);              msg="上传成功!";              upFile.setMsg(msg);            } catch (Exception e) {                  e.printStackTrace();              }             System.out.println(JSON.toJSONString(upFile));            return JSON.toJSONString(upFile);          }}