前言

最近有項目需要開發檔案打包下載功能，其中包含很多大附件，項目使用minio存儲且不在同一臺伺服器上，為了優化速度決定使用windows共用功能進行文件傳輸

SMB1.0

集成jcifs類庫，主要適用於一些老舊系統，但下載速度比較慢，僅作參考

此類庫沒有maven引用，官網地址：http://jcifs.samba.org/

註意事項：

設置jcifs.smb.client.dfs.disabled選項開啟，可以提高傳輸速度

使用NtlmPasswordAuthentication認證代替smb協議url攜帶用戶名密碼方式，避免特殊字元傳遞造成認證失敗

 public static void downloadFile(String ip, String shareFolder, String filePath, String localDir) throws Exception {
        System.setProperty("jcifs.smb.client.dfs.disabled", "true");
        String url = getFileUrl(ip, shareFolder, filePath);
        SmbFile smbFile = new SmbFile(url);
        smbFile.connect();
        FileUtil.initfloderPath(localDir);
        String localFilePath = localDir + "/" + smbFile.getName();
        BufferedInputStream buf = new BufferedInputStream(new SmbFileInputStream(smbFile));
        FileUtil.writeFile(localFilePath, FileUtil.convertStreamToByte(buf));
    }

    public static void downloadFileByAuth(String ip, String shareFolder, String userName, String password, String filePath, String localDir) throws Exception {
        System.setProperty("jcifs.smb.client.dfs.disabled", "true");
        String url = getFileUrl(ip, shareFolder, filePath);
        NtlmPasswordAuthentication auth = new NtlmPasswordAuthentication(ip, userName, password);
        SmbFile smbFile = new SmbFile(url, auth);
        smbFile.connect();
        FileUtil.initfloderPath(localDir);
        String localFilePath = localDir + "/" + smbFile.getName();
        BufferedInputStream buf = new BufferedInputStream(new SmbFileInputStream(smbFile));
        FileUtil.writeFile(localFilePath, FileUtil.convertStreamToByte(buf));
    }
    
    public static String getFileUrl(String ip, String shareFolder, String filePath) {
        return "smb://" + ip + "/" + shareFolder + "/" + filePath;
    }

SMB2.0

集成smbj類庫，適用於windows server2012及以上操作系統，預設安裝開啟無需額外配置

此類庫maven引用很久沒有發佈最新版本，需要下載代碼自行編譯，github地址：https://github.com/hierynomus/smbj

經測試，500MB文件傳輸大概比minio協議傳輸快了4秒左右，小文件傳輸速度基本保持一致

  public static void downloadFileV2(String ip, String shareFolder, String filePath, String localDir) throws Exception {
        SMBClient client = new SMBClient(SmbConfig.createDefaultConfig());
        Connection conn = client.connect(ip);
        Session session = conn.authenticate(AuthenticationContext.anonymous());
        downLoadSMB2(session, shareFolder, filePath, localDir);
    }

    public static void downloadFileByAuthV2(String ip, String shareFolder, String userName, String password, String filePath, String localDir) throws Exception {
        SMBClient client = new SMBClient(SmbConfig.createDefaultConfig());
        Connection conn = client.connect(ip);
        Session session = conn.authenticate(new AuthenticationContext(userName, password.toCharArray(), ip));
        downLoadSMB2(session, shareFolder, filePath, localDir);
    }

    private static void downLoadSMB2(Session session, String shareFolder, String filePath, String localDir) throws Exception {
        InputStream fis = null;
        FileOutputStream os = null;
        DiskShare diskShare = null;
        try {
            diskShare = (DiskShare) session.connectShare(shareFolder);
            if (!diskShare.fileExists(filePath)) {
                throw new FileNotFoundException(filePath);
            }
            if (!diskShare.isConnected())
                diskShare = (DiskShare) session.connectShare(shareFolder);

            com.hierynomus.smbj.share.File file = diskShare.openFile(filePath,
                    EnumSet.of(AccessMask.GENERIC_READ),
                    (Set) null,
                    SMB2ShareAccess.ALL,
                    SMB2CreateDisposition.FILE_OPEN,
                    (Set) null
            );
            fis = file.getInputStream();
            FileUtil.initfloderPath(localDir);
            String[] filePathList = filePath.split("\\/");
            String localFilePath = localDir + "/" + filePathList[filePathList.length - 1];
            os = new FileOutputStream(localFilePath);
            byte[] b = new byte[4096];
            int length;
            while ((length = fis.read(b)) > 0) {
                os.write(b, 0, length);
            }
        } catch (IOException e) {
            throw e;
        } finally {
            IOUtils.close(os);
            IOUtils.close(fis);
            if (diskShare != null && diskShare.isConnected()) diskShare.close();
        }
    }

445埠被禁用解決辦法

一般企業/政府項目為了系統安全會禁用445埠，而445埠禁用後文件共用功能無法使用，此時我們需要進行埠轉發，即將客戶端445埠轉發到共用伺服器埠A，共用伺服器將本地埠A轉發到445即可完成共用，具體操作步驟如下，192.168.1.164就是共用文件伺服器的內網ip

查看伺服器轉發規則

netsh interface portproxy show all

刪除伺服器轉發規則

netsh interface portproxy reset

共用文件伺服器

• 執行CMD代碼

netsh interface portproxy add v4tov4 listenport=4455 listenaddress=192.168.1.164 connectport=445 connectaddress=127.0.0.1
netsh interface portproxy add v4tov4 listenport=4455 listenaddress=127.0.0.1 connectport=445 connectaddress=127.0.0.1

客戶端伺服器

• 關閉Server服務
• CMD執行代碼

netsh interface portproxy add v4tov4 listenaddress=127.0.0.1 listenport=445 connectaddress=192.168.1.164 connectport=4455

• 重啟系統