files directly and recursively calls itself for subdirectories. Example Implementation
To download a directory in Java using the JSch library, you must implement a recursive strategy because the standard ChannelSftp.get() method only supports single-file transfers. By iterating through the remote directory's contents and handling subdirectories individually, you can mirror the entire folder structure locally. 1. Project Setup
Downloading Files from SFTP using jsch - java - Stack Overflow java jsch download directory
: You can add logic to compare timestamps ( mtime ) and only download files that have changed since the last transfer.
The first step is to create an SSH session and open an SFTP channel. To begin, add the JSch dependency to your project
To begin, add the JSch dependency to your project. Note that while the original library version 0.1.55 is common, modern forks like com.github.mwiede:jsch are often used for better security support.
: Use sftpChannel.lcd(localPath) to set the local working directory if you prefer using relative paths during the transfer. 4. Key Considerations
JSch jsch = new JSch(); Session session = jsch.getSession(username, host, 22); session.setPassword(password); // Warning: "no" is for testing; use known_hosts for production session.setConfig("StrictHostKeyChecking", "no"); session.connect(); ChannelSftp sftpChannel = (ChannelSftp) session.openChannel("sftp"); sftpChannel.connect(); Use code with caution. 3. Recursive Directory Download
: Ensure the Java application has read permissions for the remote files and write permissions for the local destination.
public void downloadDirectory(String remotePath, String localPath) throws SftpException // 1. Create local directory if it doesn't exist File localDir = new File(localPath); if (!localDir.exists()) localDir.mkdirs(); // 2. List remote directory contents Vector list = sftpChannel.ls(remotePath); for (ChannelSftp.LsEntry entry : list) String fileName = entry.getFilename(); // Skip "." and ".." to avoid infinite loops if (fileName.equals(".") Use code with caution. 4. Key Considerations