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Java

Capture the FTP Session Log

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Demonstrates the SessionLog property (with KeepSessionLog), which holds the in-memory FTP protocol conversation — commands and server replies — collected during the session.

Background: When an FTP operation fails for a non-obvious reason, the exact command/reply exchange is the most useful diagnostic there is, and SessionLog captures it verbatim once KeepSessionLog is enabled. Passwords are omitted, so it is safe to log or attach to a bug report. Over a long session it grows without bound; clear it with ClearSessionLog to bound memory or to isolate the log for one operation.

Chilkat Java Downloads

Chilkat2 Java
import com.chilkatsoft.chilkat2.ChilkatException;
import com.chilkatsoft.chilkat2.Ftp2;

public class ChilkatExample {

    public static void main(String[] args) {
        Ftp2 ftp = new Ftp2();

        ftp.setHostname("ftp.example.com");
        ftp.setUsername("myFtpLogin");

        // 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.
        ftp.setPassword("myPassword");

        // Keep an in-memory log of the FTP protocol conversation for troubleshooting.  Passwords are
        // not recorded in it.
        ftp.setKeepSessionLog(true);

        try {
            ftp.connect();

            ftp.changeRemoteDir("public_html");
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }

        // The SessionLog contains the protocol commands and server replies collected so far.
        System.out.println(ftp.getSessionLog());

        try {
            ftp.disconnect();
        } catch (ChilkatException e) {
            System.out.println(e.getLastErrorText());
            return;
        }
    }
}