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Android™

FTP Socket Buffer and Address Options

See more FTP Examples

Demonstrates the SoRcvBuf, SoSndBuf, PreferIpv6, and ClientIpAddress properties.

Background: These are low-level knobs for specific situations. Larger send/receive buffers can improve throughput on high-bandwidth, high-latency links, though the defaults suit the common case. PreferIpv6 only matters when a hostname resolves to both address families, choosing which to try first. ClientIpAddress is normally left unset; set it on a multihomed host to bind the outgoing connection to a particular local interface. Change any of these only with a concrete reason.

Chilkat Android™ Downloads

Android™
// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    boolean success = false;

    CkFtp2 ftp = new CkFtp2();

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Username("myFtpLogin");

    //  SoRcvBuf and SoSndBuf set the TCP socket receive/send buffer sizes.  The defaults are tuned for
    //  the common case; larger values can sometimes help throughput on high-latency links.
    ftp.put_SoRcvBuf(4194304);
    ftp.put_SoSndBuf(524288);

    //  PreferIpv6 (default false) chooses IPv6 over IPv4 when a hostname resolves to both.
    ftp.put_PreferIpv6(false);

    //  ClientIpAddress is normally left unset; set it on a multihomed host to bind the outgoing
    //  connection to a specific local interface.
    ftp.put_ClientIpAddress("192.168.1.50");

    //  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) {
        Log.i(TAG, ftp.lastErrorText());
        return;
        }

    Log.i(TAG, "Connected with custom socket options.");

    success = ftp.Disconnect();
    if (success == false) {
        Log.i(TAG, ftp.lastErrorText());
        return;
        }


  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}