Java

Download an FTP File to a Stream

Demonstrates the Chilkat Ftp2.GetFileToStream method, which downloads a remote file and writes its bytes to a Stream. The first argument is the remote file path and the second is the Stream, which must have a destination sink configured beforehand.

Note: The local paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: Streaming to a Stream object decouples the download from where the bytes ultimately go — a file (as here, via SinkFile), or a pipe feeding another component such as a decompressor or a hashing routine — and processes the data as it arrives rather than buffering the whole file. That keeps memory flat for large downloads and lets you chain the transfer into a processing pipeline.

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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.GetFileToStream method, which downloads a remote file and writes its
    //  bytes to a Stream.  The 1st argument is the remote file path and the 2nd is the Stream.

    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;
        }

    //  Configure the stream's destination sink before downloading.  Here the stream writes to a
    //  local file.
    CkStream fileStream = new CkStream();
    fileStream.put_SinkFile("qa_output/report.pdf");

    success = ftp.GetFileToStream("public_html/report.pdf",fileStream);
    if (success == false) {
        System.out.println(ftp.lastErrorText());
        return;
        }

    System.out.println("Downloaded to stream.");

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