sftp作为临时的文件存储位置，在某些场合还是有其应景的，比如对账文件存放。需要提供一个上传的工具类。实现方法参考下：
pom.xml中引入类库：
<dependency> <groupId>com.jcraft</groupId> <artifactId>jsch</artifactId> <version>0.1.54</version> </dependency>
sftp工具类和使用命令行是一样的操作方法，上传下载如下：
public class SftpUploadTest { private ChannelSftp sftp = null; private Session sshSession = null; private String username; private String password; private String host; private int port; public SftpUploadTest(String username, String password, String host, int port) { this.username = username; this.password = password; this.host = host; this.port = port; } /** * 连接sftp服务器 * * @return ChannelSftp sftp连接实例 */ public ChannelSftp connect() { info("-->sftp连接开始>>>>>> " + host + ":" + port + " >>>username=" + username); JSch jsch = new JSch(); try { jsch.getSession(username, host, port); sshSession = jsch.getSession(username, host, port); sshSession.setPassword(password); Properties properties = new Properties(); properties.put("StrictHostKeyChecking", "no"); sshSession.setConfig(properties); sshSession.connect(); Channel channel = sshSession.openChannel("sftp"); channel.connect(); sftp = (ChannelSftp) channel; info(" ftp Connected to " + host + ":" + port); } catch (JSchException e) { throw new RuntimeException("sftp连接失败", e); } return sftp; } /** * 下载单个文件，如果指定文件名，则下载到文件名否则保持原有文件名 * * @param remoteFilePath 远程文件路径 /tmp/xxx.txt || xxx.txt.zip * @param localFilePath 本地文件路径 如 D:\\xxx.txt * @return 下载的文件 */ public File downloadFile(String remoteFilePath, String localFilePath) { info(">>>>>>>>>downloadFile--ftp下载文件" + remoteFilePath + "开始>>>>>>>>>>>>>"); connect(); String remoteFileName = ""; // 远端目录确定以 / 作为目录格式 String rFileSeparator = "/"; int rDirNameSepIndex = remoteFilePath.lastIndexOf(rFileSeparator) + 1; String rDir = remoteFilePath.substring(0, rDirNameSepIndex); remoteFileName = remoteFilePath.substring(rDirNameSepIndex); if(localFilePath.endsWith(File.separator)) { localFilePath = localFilePath + (localFilePath.endsWith(File.separator) ? remoteFileName : "/" + remoteFileName); } File file = null; OutputStream output = null; try { file = new File(localFilePath); if (file.exists()) { file.delete(); } file.createNewFile(); sftp.cd(rDir); output = new FileOutputStream(file); sftp.get(remoteFileName, output); info("===DownloadFile:" + remoteFileName + " success from sftp."); } catch (SftpException e) { error("ftp下载文件失败", e); } catch (FileNotFoundException e) { error("本地目录异常，请检查" + file.getPath(), e); } catch (IOException e) { error("创建本地文件失败" + file.getPath(), e); } finally { if (output != null) { try { output.close(); } catch (IOException e) { e.printStackTrace(); } } disconnect(); } info(">>>>>>>>>downloadFile--ftp下载文件结束>>>>>>>>>>>>>"); return file; } /** * 上传单个文件，如果指正下载文件名则使用，否则保留原有文件名 * * @param remoteFilePath 远程文件路径 /tmp/xxx.txt ||xxx.txt.zip * @param uploadFilePath 要上传的文件 如：D:\\test\\xxx.txt */ public void uploadFile(String remoteFilePath, String uploadFilePath) { info(" begin uploadFile from:" + uploadFilePath + ", to: " + remoteFilePath); FileInputStream in = null; connect(); String remoteFileName = ""; String remoteDir = remoteFilePath; String localFileName = ""; // 远端目录确定以 / 作为目录格式 String rFileSeparator = "/"; if(remoteFilePath.endsWith(rFileSeparator)) { localFileName = uploadFilePath.substring(uploadFilePath.lastIndexOf(File.separator) + 1); remoteFileName = localFileName; } else { int fileNameDirSep = remoteFilePath.lastIndexOf(rFileSeparator) + 1; remoteDir = remoteFilePath.substring(0, fileNameDirSep); remoteFileName = remoteFilePath.substring(fileNameDirSep); } try { sftp.cd(remoteDir); } catch (SftpException e) { try { sftp.mkdir(remoteDir); sftp.cd(remoteDir); } catch (SftpException e1) { error("ftp创建文件路径失败，路径为" + remoteDir); throw new RuntimeException("ftp创建文件路径失败" + remoteDir); } } File file = new File(uploadFilePath); try { in = new FileInputStream(file); sftp.put(in, remoteFileName); } catch (FileNotFoundException e) { error("文件不存在-->" + uploadFilePath); } catch (SftpException e) { error("sftp异常-->", e); } finally { if (in != null) { try { in.close(); } catch (IOException e) { info("Close stream error." + e.getMessage()); } } disconnect(); } info(">>>>>>>>>uploadFile--ftp上传文件结束>>>>>>>>>>>>>"); } /** * 关闭连接 */ public void disconnect() { if (this.sftp != null) { if (this.sftp.isConnected()) { this.sftp.disconnect(); this.sftp = null; info("sftp 连接已关闭！"); } } if (this.sshSession != null) { if (this.sshSession.isConnected()) { this.sshSession.disconnect(); this.sshSession = null; info("sshSession 连接已关闭！"); } } } private void info(String msg) { System.out.println("info: " + msg); } private void error(String msg) { error(msg, null); } private void error(String msg, Throwable e) { System.out.println("error: " + msg); if(e != null) { e.printStackTrace(); } } public static void main(String[] args) throws Exception { SftpUploadTest uploadTest = new SftpUploadTest("root", "123", "10.40.10.17", 52766); uploadTest.uploadFile("/tmp/" + "readme-" + System.currentTimeMillis() + ".txt", "C:\\Users\\xx\\Desktop\\sample\\readme.txt"); uploadTest.downloadFile("/tmp/readme.txt", "C:\\Users\\xx\\Desktop\\sample\\readme-" + System.currentTimeMillis() + ".txt"); } }
使用时，可根据需要进行连接的适时释放！也可能为了安全需要，添加一些额外的安全指令！
sftp文件操作的命令罗列如下参考：
sftp常用的为上传下载
# get # 从远程服务器上下载一个文件存放到本地，如下： # 先通过lcd切换到本地那个目录下，然后通过get file >> lcd d:\ #表示切换到本地的d盘下 >> get ./test.sql #这样就将当前文件下载本地的d盘下 # put # 是将本地的文件上传到远程服务器上，如下： >> put #在windows下弹出选择文件的窗口 # lcd # 先通过lcd切换到本地那个目录下 >> lcd c:\ #表示切换到本地的c盘下 # lls #显示当前目录下的所有文件 >> pwd #显示当前目录