SpringBoot搭建文件服务器

系统管理员 2022-11-20 04:50 396阅读 0赞

#### 1、代码实现 FileUtils ####

package com.xdx97.frame.common.utils;
    
    import org.springframework.web.multipart.MultipartFile;
    
    import javax.servlet.http.HttpServletResponse;
    import java.io.*;
    import java.net.HttpURLConnection;
    import java.net.URL;
    import java.net.URLConnection;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.UUID;
    
    /** * 文件操作相关 */
    public class FileUtils { 
    
        /** * 文件地址，按照年月日存储 * * filePath 文件上传路径 * uploadFolder 文件夹名称 */
        private static String filePath;
        private static String fileFolder = "uploadFolder";
        static { 
            try { 
                filePath =  new File("").getCanonicalPath() + "/"+fileFolder+"/";
            }catch (Exception e){ 
                throw new RuntimeException("获取文件基本路径失败");
            }
        }
    
        /** * 文件上传 单个 */
        public static String upload( MultipartFile file){ 
            try { 
                String fileName = file.getOriginalFilename();
                String suffix = fileName.split("\\.")[1];
                String newFileName = DateUtils.getYear() + "/" +
                                     DateUtils.getMonth() + "/" +
                                     DateUtils.getDay() + "/" +
                                     UUID.randomUUID().toString() + "." + suffix;
                String newPath = filePath + newFileName;
                // 判断当前文件夹是否存在
                File oldFile = new File(newPath);
                if (!oldFile.getParentFile().exists()){ 
                    oldFile.getParentFile().mkdirs();
                }
                File file2 = new File(newPath);
                file.transferTo(file2);
                return newFileName;
            } catch (IOException e) { 
                throw new RuntimeException("文件上传失败");
            }
        }
    
        /** * 文件上传 多个 */
        public static List<String> uploads( List<MultipartFile> files){ 
            List<String> result = new ArrayList<>();
            for (MultipartFile file : files){ 
                result.add(upload(file));
            }
            return result;
        }
    
        /** * 文件下载 */
        public static void download(String fileName, HttpServletResponse response) { 
            OutputStream toClient = null;
            try { 
                // path是指欲下载的文件的路径。
                File file = new File(filePath + fileName);
                // 取得文件名。
                String filename = file.getName();
                // 取得文件的后缀名。
                String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();
                // 以流的形式下载文件。
                InputStream fis = new BufferedInputStream(new FileInputStream(filePath + fileName));
                byte[] buffer = new byte[fis.available()];
                fis.read(buffer);
                fis.close();
                // 清空response
                response.reset();
                // 如果是图片就预览，不是图片就下载
                if (fileName.endsWith("jpg") || fileName.endsWith("png") || fileName.endsWith("gif")){ 
                    response.setHeader("Content-Type", "image/jpeg");
                }else { 
                    response.addHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes()));
                    response.setContentType("application/octet-stream; charset=utf-8");
    
                }
                response.addHeader("Content-Length", "" + file.length());
                response.setHeader("Access-Control-Allow-Origin", "*");
                 toClient = new BufferedOutputStream(response.getOutputStream());
                toClient.write(buffer);
    
            } catch (IOException ex) { 
                ex.printStackTrace();
            }finally { 
                try { 
                    toClient.flush();
                    toClient.close();
                }catch (Exception e){ 
                    e.printStackTrace();
                    System.out.println("文件上传关闭流失败！");
                }
            }
        }
    
        /** * 从网络中下载文件 * * @param filePath 网络文件地址 */
        public static void downloadByNetwork(String filePath,HttpServletResponse response){ 
            InputStream inputStream = null;
            try { 
                URL url = new URL(filePath);
                HttpURLConnection con = (HttpURLConnection) url.openConnection();
                int httpRequestCode = con.getResponseCode();
                if(httpRequestCode != 200){ 
                    throw new Exception("文件下载错误，错误码："+httpRequestCode);
                }
                // 将文件读入文件流
                inputStream = con.getInputStream();
                // 下载文件的名称
                String finalFileName = UUID.randomUUID().toString();
                // 设置HTTP响应头
                // 重置 响应头
                response.reset();
                // 告知浏览器下载文件，而不是直接打开，浏览器默认为打开
                response.setContentType(URLConnection.getFileNameMap().getContentTypeFor(filePath));
                response.addHeader("Content-Disposition", "attachment;filename=" + finalFileName);
                // 循环取出流中的数据
                byte[] b = new byte[1024];
                int len;
                while ((len = inputStream.read(b)) > 0) { 
                    response.getOutputStream().write(b, 0, len);
                }
    
            }catch (Exception e){ 
                throw new RuntimeException("从网络中下载文件失败");
            }finally { 
                try { 
                    inputStream.close();
                    response.getOutputStream().close();
                }catch (Exception e){ 
                    throw new RuntimeException("文件流关闭失败");
                }
            }
        }
    }

#### 2、视频讲解 ####

[https://www.bilibili.com/video/BV1kf4y1i761?p=7][https_www.bilibili.com_video_BV1kf4y1i761_p_7]

[https_www.bilibili.com_video_BV1kf4y1i761_p_7]: https://www.bilibili.com/video/BV1kf4y1i761?p=7