Java

Resolve an Absolute Remote Path with SFTP RealPath

Demonstrates the Chilkat SFtp.RealPath method, which asks the server to canonicalize a path and returns the resulting absolute remote path. The first argument is the original path and the second is an optional compose path (SFTP v5 or later); pass an empty string when no composition is needed.

Background: The server — not the client — owns the remote filesystem's layout, so path canonicalization must happen on the server. RealPath resolves ., .., and symbolic links into a single absolute path, which is the reliable way to learn the session's home directory (canonicalize .) or to turn a relative path into an absolute one before storing or displaying it. On SFTP v5 and later, the compose path can additionally join or override the original.

Chilkat Java Downloads

Download Chilkat for Java

Chilkat2 Java

import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.SFtp;

public class ChilkatExample {

    public static void main(String[] args) {
        // Demonstrates the SFtp.RealPath method, which asks the server to canonicalize a path and
        // returns the resulting absolute remote path.  The 1st argument is the original path and the
        // 2nd is an optional compose path (SFTP v5+), which may be an empty string.

        SFtp sftp = new SFtp();

        // Step 1: Connect the SSH transport.  Port 22 is the usual port.
        int port = 22;
        try {
            sftp.connect("sftp.example.com", port);
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // Normally you would not hard-code the password in source.  You should instead obtain it
        // from an interactive prompt, environment variable, or a secrets vault.
        String password = "mySshPassword";

        String homeDir;
        try {
            sftp.authenticatePw("mySshLogin", password);

            // Step 3: Open the SFTP subsystem.  This must be done after authentication and before any
            // file or directory operations.
            sftp.initializeSftp();

            // Resolve "." to the absolute path of the session's default (home) directory.  No compose path
            // is needed, so the 2nd argument is an empty string.
            homeDir = sftp.realPath(".", "");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Home directory: " + homeDir);

        // Canonicalize a relative path with "..", resolving it to an absolute path.
        String resolved;
        try {
            resolved = sftp.realPath("subdir/../otherdir", "");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        System.out.println("Resolved path: " + resolved);

        sftp.disconnect();
    }
}