上传与下载

将网页中的表格导入或者下载到本地，并保存为xls格式

import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.usermodel.XSSFWorkbook;

class DownLoadXls{
    
    //excle生成临时目录
    private String templateDir = "d:/"

    //打包成一个方法了
    public void exportUser(HttpServletResponse response){
        List<User> userlist = userService.findAllUser();
        //生成excel，并写入本地和请求的客户端
        Workbook workbook = new XSSFWorkbook();
        workbook.createSheet();
        Sheet sheet0 = workbook.getSheetAt(0);
        Row headRow = sheet0.createRow(0);
        //设置单元格-username
        headRow.createCell(0, Cell.CELL_TYPE_STRING).setCellValue("姓名");
        //设置单元格-password
        headRow.createCell(1, Cell.CELL_TYPE_STRING).setCellValue("密码");
        //设置单元格-birthday
        headRow.createCell(2, Cell.CELL_TYPE_NUMERIC).setCellValue("生日");
        for(int i = 0;i < userlist.size();i++){
            User user = user.get(i);
            Row curRow = sheet0.createRow(i+1);
            curRow.createCell(0,Cell.CELL_TYPE_STRING).setCellValue(user.getUserName());
            curRow.createCell(1,Cell.CELL_TYPE_STRING).setCellValue(user.getPassWord());
            ZoneId zoneId = ZoneId.systemDefault();
            Instant instant = user.getBirthday().atZone(zoneId).toInstant();
            String birthdayTime = DatwTimeUtil.datetimeToStringHH(Date.from(instant));
            curRow.createCell(2,Cell.CELL_TYPE_NUMERIC).setCellValue(birthdayTime);
        }
        BufferedOutputStream out = null;
        try{
            response.reset();
            response.setCharacterEncoding("utf-8");
            //Content-disposition告诉浏览器以下载的形式打开
            //URLEncoder.encode("user.xlsx",StandardCharsets.UTF_8.name());
            response.setHeader("Content-disposition","attachment;filename="+getExportFileName());
            //application/ms-excel;charset=utf-8 告诉浏览器下载的文件是excel
            response.setContentType("application/ms-excel");
            workbook.write(out);
            out.flush();
        }catch(IOException e){
            e.printStackTrace();
        }finally{
            try{
                out.close();
            }catch(IOException e){
            }
        }
    }
}

上传图片，存在数据库中的是图片路径，可以不使用ajax请求，参考：https://www.cnblogs.com/yvanBk/p/8953885.html

    @GET
    @POST
    @Path("/uploadPicture")
    @Produces("application/json;charset=UTF-8")
    @Consumes("multipart/form-data")
    public String uploadPicture(@Context HttpServletRequest request, @Context HttpServletResponse response){
        JSONObject resultJson = new JSONObject();
        String imgName=null;//给图片定义名称
        String imgPath = null;//给图片指定的上传路径
        String strusercode=null;
        List<Map<String,Object>> list = new ArrayList<Map<String,Object>>();
        try{
            //创建服务器路径存储图片
            imgPath=THESERVERURL+"broadcast\";
            //创建文件夹
            File file = new File(imgPath);
            if (!file.exists()){// 创建文件夹
                file.mkdirs();
            }else{
                //删除文件中的所有图片
                String name[]=file.list();
                for (int i=0; i<name.length; i++){  
                    File f=new File(imgPath,name[i]);//此时就可得到文件夹中的文件  
                    f.delete();//删除文件  
                }  
            }
            DiskFileItemFactory factory = new DiskFileItemFactory(); // 设置工厂
            factory.setRepository(new File(imgPath)); // 设置文件存储位置
            factory.setSizeThreshold(1024 * 1024); // 设置大小，如果文件小于设置大小的话，放入内存中，如果大于的话则放入磁盘中,单位是byte
            ServletFileUpload upload = new ServletFileUpload(factory);
            upload.setHeaderEncoding("utf-8"); // 这里就是中文文件名处理的代码，其实只有一行
            List<FileItem> listform = upload.parseRequest(request);
            if (listform != null && !listform.isEmpty()){
                int sort=0;
                for (FileItem fileItem : listform){
                    sort++;
                    Map<String,Object> map =new HashMap<String,Object>();
                    // 判断表单数据是否为普通字段 不是则为图片字段
                    if (fileItem.isFormField()){
                        String fieldName = fileItem.getFieldName();// 获取表单字段名称
                        String value = fileItem.getString("utf-8");// 获取表单字段值
                        strusercode=value;//获取用户编码
                    }else{
                        // 上传图片的保存 
                        String value = fileItem.getName();//值
                        //String fieldName = fileItem.getFieldName();// 获取表单字段名称
                        if(value!=null && !"".equals(value)){
                            // 保存的图片名称  currentTimeMillis时间搓
                            imgName = System.currentTimeMillis()+ fileItem.getName().substring(fileItem.getName().lastIndexOf("."));
                            // 保存(写)
                            fileItem.write(new File(imgPath, imgName));
                            map.put("broadcastUrl", "broadcast/" + imgName);//图片路径
                            map.put("booleans", "1");//是否显示图片
                            map.put("sort", sort);//图片路径
                            map.put("dtnoticetime", PublicTools.gettime());//上传时间
                            list.add(map);
                        }
                    }
                }
                //删除表里面的图片记录
                userDaoImpl.delete("delete from t_broadcast");
                //往表里插入数据
                userDaoImpl.insertinto(BroadcastSql.insertSql(list, strusercode));
            }else{
                return this.returnError(resultJson,ResMessage.Server_Abnormal.code,request);
            }
        } catch (Exception e){
            logger.info("登录信息异常",e);
            return this.returnError(resultJson,ResMessage.Server_Abnormal.code,request);
        }
        return this.response(resultJson, request);
    }

上传视频，参考：https://blog.csdn.net/qq791007/article/details/73332136

@ResponseBody
@RequestMapping("upload")
public Map upload(HttpServletRequest request,
 　　　　　　　　　　@RequestParam(value = "myFile", required = false) MultipartFile[] files) {
    Map map =new HashMap();
    try {
        for(int i=0;i<files.length;i++){
            FileUploadUtils.upload(request, files[i]);
        }
        map.put("code","1");
        map.put("msg","上传成功！");
    } catch (Exception e) {
        map.put("code","0");
        map.put("msg","上传失败！");
        e.printStackTrace();
    }
    return map;
}

public class FileUploadUtils {
    //默认大小 50M
    public static final long DEFAULT_MAX_SIZE = 52428800;
    //默认上传的地址
    public static  String defaultBaseDir = "upload";

    public static final String upload(HttpServletRequest request, MultipartFile file)throws Exception{
        String filename = extractFilename(file, defaultBaseDir);
        File desc = getAbsoluteFile(extractUploadDir(request), filename);
        file.transferTo(desc);
        return filename;
    }
    private static final File getAbsoluteFile(String uploadDir, String filename) throws IOException {
        if(uploadDir.endsWith("/")) {
            uploadDir = uploadDir.substring(0, uploadDir.length() - 1);         }
        if(filename.startsWith("/")) {
            filename = filename.substring(0, uploadDir.length() - 1);        }
        System.out.println(uploadDir + "/" + filename);
        File desc = new File(uploadDir + "/" + filename);
        if(!desc.getParentFile().exists()) {
            desc.getParentFile().mkdirs();        }
        if(!desc.exists()) {
            desc.createNewFile();        }
        return desc;
    }

    public static final String extractFilename(MultipartFile file, String baseDir) throws UnsupportedEncodingException {
        String filename = file.getOriginalFilename();
        int slashIndex = filename.indexOf("/");
        if (slashIndex >= 0) {
            filename = filename.substring(slashIndex + 1);
        }
        filename = baseDir + "/" + filename;
        return filename;
    }
    public static final String extractUploadDir(HttpServletRequest request) {
        return request.getServletContext().getRealPath("/");
    }
}

下载视频

@ResponseBody
@RequestMapping("getMp4")
public void getMp4(String cateogry,
                    HttpServletRequest request,
                    HttpServletResponse response) throws IOException {

    if(StringUtils.isEmpty(cateogry)) {
        cateogry = "";
    }
    String os = System.getProperty("os.name");
    String path="";
    if(os.toLowerCase().startsWith("win")){
        path="D:/";
    }else{
        path="/home/work/";
    }

    String fileName = path+cateogry;

    File file = new File(fileName);

    //判断文件是否存在如果不存在就返回默认图标
    if(!(file.exists() && file.canRead())) {
        file = new File(path+"company/root.png");
    }

    FileInputStream inputStream = new FileInputStream(file);
    byte[] data = new byte[(int)file.length()];
    int length = inputStream.read(data);
    inputStream.close();
    response.setContentType("video/mpeg4");// 设定输出的类型
    response.setHeader("Content-Disposition", "attachment;filename="  + fileName);

    OutputStream stream = response.getOutputStream();
    stream.write(data);
    stream.flush();
    stream.close();
}