File Existence Check

Testing to see if a file exists on the FTP server. The GetSizeByName method is a convenient way to check if a file exists. It will return -1 if the file does not exist, otherwise it returns the size of the file in bytes.

Download Chilkat Java Library

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[])
  {
    CkFtp2 ftp = new CkFtp2();

    boolean success;

    //  Any string unlocks the component for the 1st 30-days.
    success = ftp.UnlockComponent("Anything for 30-day trial");
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
    }

    ftp.put_Hostname("ftp.***.com");
    ftp.put_Username("***");
    ftp.put_Password("***");

    //  Connect and login to the FTP server.
    success = ftp.Connect();
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
    }

    //  Set the current remote directory to where the file is located:
    success = ftp.ChangeRemoteDir("/something");
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
    }

    //  Test to see if the file exists by getting the file size by name.
    //  If a -1 is returned, the file does not exist.
    int fileSize;
    fileSize = (int) ftp.GetSizeByName("test123.txt");
    if (fileSize < 0) {
        System.out.println("file does not exist");
    }
    else {
        System.out.println("file exists and is "
             + fileSize + " bytes in size");
    }

    ftp.Disconnect();
  }
}