File transfer protocol (FTP) is a used to transfer files between clients and servers.
The apache commons API provides the org.apache.commons.net.ftp.FTPClient which helps us to carry out various FTP operations very easily.
Step 1:
Download the commons-net-3.4 jar file from here and put it in your project build path:
http://central.maven.org/maven2/commons-net/commons-net/3.4/commons-net-3.4.jar
For Maven and other dependencies:
Step 2:
Below is a very simple example of FTP in Java.
- Please change the ftpUrl and defaultPort to your own.
- Use changeWorkingDirectory method to go to the directory of the file before accessing the file. Default path after login is "ROOT" directory.
- In retrieveFileStream pass the file name
File: ReadFtpFileExample.java
package net.codermag.sample;
import java.io.InputStream;
import java.util.Scanner;
import org.apache.commons.net.ftp.FTPClient;
public class ReadFtpFileExample {
public static void main(String[] args) {
String ftpUrl = "ftp.funet.fi";
int defaultPort = 21;
String user = "username";
String pass = "password";
try {
//Opening the FTP connection and logging in
FTPClient ftpClient = new FTPClient();
ftpClient.connect(ftpUrl, defaultPort);
ftpClient.login(user, pass);
ftpClient.enterLocalPassiveMode();
//if the file is not in root we need to change directory
ftpClient.changeWorkingDirectory("/pub/standards/RFC/");
InputStream inputStream = ftpClient.retrieveFileStream("rfc959.txt");
Scanner sc = new Scanner(inputStream);
//Reading the file line by line and printing the same
while (sc.hasNextLine())
System.out.println(sc.nextLine());
//Closing the channels
sc.close();
inputStream.close();
}
catch (Exception e)
{
e.printStackTrace();
}
}
}