Use the FTP Client : Ftp « Network Protocol « Java






Use the FTP Client

 

/*
 * Copyright 2001-2005 The Apache Software Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package examples;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import org.apache.commons.net.ftp.FTP;
import org.apache.commons.net.ftp.FTPClient;
import org.apache.commons.net.ftp.FTPConnectionClosedException;
import org.apache.commons.net.ftp.FTPReply;

/***
 * This is an example program demonstrating how to use the FTPClient class.
 * This program connects to an FTP server and retrieves the specified
 * file.  If the -s flag is used, it stores the local file at the FTP server.
 * Just so you can see what's happening, all reply strings are printed.
 * If the -b flag is used, a binary transfer is assumed (default is ASCII).
 * <p>
 * Usage: ftp [-s] [-b] <hostname> <username> <password> <remote file> <local file>
 * <p>
 ***/
public class ftp
{

    public static final String USAGE =
        "Usage: ftp [-s] [-b] <hostname> <username> <password> <remote file> <local file>\n" +
        "\nDefault behavior is to download a file and use ASCII transfer mode.\n" +
        "\t-s store file on server (upload)\n" +
        "\t-b use binary transfer mode\n";

    public static final void main(String[] args)
    {
        int base = 0;
        boolean storeFile = false, binaryTransfer = false, error = false;
        String server, username, password, remote, local;
        FTPClient ftp;

        for (base = 0; base < args.length; base++)
        {
            if (args[base].startsWith("-s"))
                storeFile = true;
            else if (args[base].startsWith("-b"))
                binaryTransfer = true;
            else
                break;
        }

        if ((args.length - base) != 5)
        {
            System.err.println(USAGE);
            System.exit(1);
        }

        server = args[base++];
        username = args[base++];
        password = args[base++];
        remote = args[base++];
        local = args[base];

        ftp = new FTPClient();
        ftp.addProtocolCommandListener(new PrintCommandListener(
                                           new PrintWriter(System.out)));

        try
        {
            int reply;
            ftp.connect(server);
            System.out.println("Connected to " + server + ".");

            // After connection attempt, you should check the reply code to verify
            // success.
            reply = ftp.getReplyCode();

            if (!FTPReply.isPositiveCompletion(reply))
            {
                ftp.disconnect();
                System.err.println("FTP server refused connection.");
                System.exit(1);
            }
        }
        catch (IOException e)
        {
            if (ftp.isConnected())
            {
                try
                {
                    ftp.disconnect();
                }
                catch (IOException f)
                {
                    // do nothing
                }
            }
            System.err.println("Could not connect to server.");
            e.printStackTrace();
            System.exit(1);
        }

__main:
        try
        {
            if (!ftp.login(username, password))
            {
                ftp.logout();
                error = true;
                break __main;
            }

            System.out.println("Remote system is " + ftp.getSystemName());

            if (binaryTransfer)
                ftp.setFileType(FTP.BINARY_FILE_TYPE);

            // Use passive mode as default because most of us are
            // behind firewalls these days.
            ftp.enterLocalPassiveMode();

            if (storeFile)
            {
                InputStream input;

                input = new FileInputStream(local);

                ftp.storeFile(remote, input);

                input.close();
            }
            else
            {
                OutputStream output;

                output = new FileOutputStream(local);

                ftp.retrieveFile(remote, output);

                output.close();
            }

            ftp.logout();
        }
        catch (FTPConnectionClosedException e)
        {
            error = true;
            System.err.println("Server closed connection.");
            e.printStackTrace();
        }
        catch (IOException e)
        {
            error = true;
            e.printStackTrace();
        }
        finally
        {
            if (ftp.isConnected())
            {
                try
                {
                    ftp.disconnect();
                }
                catch (IOException f)
                {
                    // do nothing
                }
            }
        }

        System.exit(error ? 1 : 0);
    } // end main

}


           
         
  








apache_net.zip( 395 k)

Related examples in the same category

1.Upload file to FTP server
2.Connect to FTP server
3.Get list of files from FTP server
4.Download file from FTP server
5.Delete file from FTP server
6.Running the edtFTPj demo
7.Implements a Java FTP client from socket and RFC
8.Graphical Ftp clientGraphical Ftp client
9.Ftp client demonstration
10.Ftp client gets server file size
11.Establish ftp connection
12.Use the FTPClient: server file transfer
13.A simple Java tftp client