(Java) Delete Local Files that Do Not Exist on the FTP Server

Demonstrates how to get a list of local files in a directory tree that do not exist on the FTP server.

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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[])
  {
    // This example requires the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    CkFtp2 ftp = new CkFtp2();

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Username("login");
    ftp.put_Password("password");

    ftp.put_KeepSessionLog(true);

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

    // Set the current remote directory to the root of
    // the remote tree to be compared.
    success = ftp.ChangeRemoteDir("abc123");
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
        }

    // Recursively descend the local directory tree
    // and find the files that exist locally but not remotely.
    // These are the files what would be uploaded via
    // the SyncRemoteTree method call with mode = 1.
    // (Mode 1 would upload all files that do not exist on the FTP server.)

    // The actual uploading is avoided by setting the preview-only argument to true.
    int mode = 1;
    boolean descendTree = true;
    boolean previewOnly = true;
    success = ftp.SyncRemoteTree2("/temp/abc123",mode,descendTree,previewOnly);
    if (success != true) {
        System.out.println(ftp.lastErrorText());
        return;
        }

    // The files what would've been uploaded are now available in the SyncPreview property,
    // which contains a list of local file paths, one per line.
    // A program can iterate over them like this:
    CkStringArray sa = new CkStringArray();
    sa.LoadFromText(ftp.syncPreview());

    CkFileAccess fac = new CkFileAccess();

    int numFiles = sa.get_Count();
    int i = 0;
    String localFilePath;
    while ((i < numFiles)) {
        localFilePath = sa.getString(i);
        System.out.println(localFilePath);

        // An application can delete the file using Chilkat's file access object,
        // or it can choose to use the native file API available in the programming language:
        success = fac.FileDelete(localFilePath);
        if (success != true) {
            System.out.println("Failed to delete: " + localFilePath);
            }

        i = i+1;
        }

    success = ftp.Disconnect();
  }
}