télécharger le fichier/répertoire ftp

En utilisant commons-net-3.0.jar fourni par Apache, vous pouvez communiquer avec le Serveur FTP.

FTPUtils Classe est d'avoir de base comme connexion,de déconnexion,de télécharger et de méthodes de téléchargement.
et FTPMain ayant principale méthode pour télécharger le fichier.

FTPUtils:

package com.ftpclient.test;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPClient;
public class FTPUtils {
public static void ftpConnect(FTPClient ftpclient, String host, String username, String password) throws IOException {
System.out.println("FTPUtils :: Logging in FTP..");
try{
ftpclient.connect(host);
if (!ftpclient.login(username, password)) {
throw new IOException("Supplied wrong credentials to FTP Server");
}
if (ftpclient.getReplyCode() != 0) {
System.out.println(ftpclient.getReplyString());
}
}catch(IOException ioe){
ioe.printStackTrace();
System.out.println("FTP Client is not able to Connect to host");
throw new IOException("FTP Client is not able to Connect to host");
}
System.out.println("FTPUtils :: FTP Login Successful..");
}
/**
* disconnect to FTP server
* 
* @param ftpclient is Object which is having details of FTP server like IP, user name and password
* @throws IOException throws Exception
*/
public static void ftpDisConnect(FTPClient ftpclient) throws IOException {
System.out.println("FTPUtils :: FTP Logging out..");
ftpclient.logout();
ftpclient.disconnect();
System.out.println("FTPUtils :: FTP Disconnected Successfully..");
}
/**
* download's file from source path to destination path by using FTP Client.
* 
* @param ftpclient is Object which is having details of FTP server like IP, user name and password
* @param sourcePath is String from where to download's file
* @param destinationPath is String to where to download's file.
* @return boolean true if download's with out any fail else false
* @throws IOException will throw any problem with file system
*/
public static boolean downloadFile(FTPClient ftpclient, String sourcePath, String destinationPath) throws IOException {
System.out.println("FTPUtils :: RemoteFile download starts ..FTP SOURCE " + sourcePath + " DESTINATION " + destinationPath);
FileOutputStream fos = null;
boolean result = false;
try{            
ftpclient.setFileTransferMode(FTP.BINARY_FILE_TYPE);
ftpclient.setFileType(FTP.BINARY_FILE_TYPE);
File fDestination = new File(destinationPath);
fos = new FileOutputStream(fDestination);
result = ftpclient.retrieveFile(sourcePath, fos);
if (result) {
System.out.println("FTPUtils :: RemoteFile download Completed..FTP " + sourcePath);
}
}catch(IOException ioe){
ioe.printStackTrace();
System.out.println("FTP is not able to Download the files from host");
throw new IOException("FTP is not able to Download the files from host");
}finally{
fos.close();
}
return result;
}
/**
* @param ftpclient
* @param sourcePath
* @param destinationPath
* @throws IOException
*/
public static void uploadFile(FTPClient ftpclient, String sourcePath, String destinationPath) throws IOException {
FileInputStream fis = null;
try {
//
//Create an InputStream of the file to be uploaded
//
fis = new FileInputStream(sourcePath);
//
//Store file to server
//
ftpclient.storeFile(destinationPath, fis);
}catch(IOException ioe){
ioe.printStackTrace();
System.out.println("FTP is not able to upload the files from host");
throw new IOException("FTP is not able to upload the files from host");
}finally{
fis.close();
}
}
}

FTPMain:

import java.io.IOException;
import org.apache.commons.net.ftp.FTPClient;
public class FTPMain {
public static void main(String[] str){
FTPClient ftpclient = new FTPClient();
try {
FTPUtils.ftpConnect(ftpclient, "ipaddress", "username", "password");
FTPUtils.uploadFile(ftpclient, "sourcePath", "destinationPath");
} catch (IOException e) {
//TODO Auto-generated catch block
e.printStackTrace();
}
}
}