Java

Get an FTP Listing Entry's Last-Modified Time

Demonstrates the Chilkat Ftp2.GetLastModifiedTimeStr method, which returns the last-modified time of a cached directory-listing entry as an RFC 822 date-time string. The only argument is a zero-based index.

Background: The last-modified time is the workhorse timestamp: it updates whenever a file's contents change and is what sync and mirror logic compares to decide whether a file needs re-transferring. It is the most reliably reported of the three across FTP servers, and the RFC 822 string carries a timezone so comparisons are well defined.

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Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    //  Demonstrates the Ftp2.GetLastModifiedTimeStr method, which returns the last-modified time of a
    //  cached directory-listing entry as an RFC 822 date-time string.  The only argument is a
    //  zero-based index.

    CkFtp2 ftp = new CkFtp2();

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Username("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.put_Password("myPassword");

    success = ftp.Connect();
    if (success == false) {
        System.out.println(ftp.lastErrorText());
        return;
        }

    success = ftp.ChangeRemoteDir("public_html");
    if (success == false) {
        System.out.println(ftp.lastErrorText());
        return;
        }

    //  GetDirCount retrieves the directory listing on the first call and returns the number of
    //  entries.  A negative return indicates failure.
    int n = ftp.GetDirCount();
    if (n < 0) {
        System.out.println(ftp.lastErrorText());
        return;
        }

    int i;
    for (i = 0; i <= n - 1; i++) {
        String name = ftp.getFilename(i);

        //  The value is an RFC 822 string such as "Fri, 21 Nov 1997 09:55:06 -0600".
        String lastModified = ftp.getLastModifiedTimeStr(i);
        System.out.println(name + "  modified " + lastModified);
        }

    success = ftp.Disconnect();
    if (success == false) {
        System.out.println(ftp.lastErrorText());
        return;
        }
  }
}