Introduction
I was cleaning up my hard drive this Memorial Day weekend when I found a bunch of code I wrote many years ago. It is funny how hindsight is 20/20. The old code examples I found were in some cases awful by today’s standards. At the time, I thought it looked pretty good. I guess as we celebrate 25 years of Java and me coding it, we should look at some code from dusty days past.
Code
The code was originally written for Apache commons-net-1.3.0, but it still works and not a lot has changed with Apache… or FTP for decades. Let’s look at some code. I did update some of it from its original state. I couldn’t let it pass. It may have a little Java 8+ “enhancements”.
/*
* FTPTransfer.java
*
* Created on January 23, 2004, 8:20 AM
*/
/*
* Copyright (C) 2004 John Yeary. All Rights Reserved.
*
* THIS SOFTWARE IS PROVIDED "AS IS," WITHOUT A WARRANTY OF ANY KIND. ALL
* EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES,
* INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. JOHN YEARY AND
* ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES OR LIABILITIES
* SUFFERED BY LICENSEE AS A RESULT OF OR RELATING TO USE, MODIFICATION
* OR DISTRIBUTION OF THE SOFTWARE OR ITS DERIVATIVES. IN NO EVENT WILL
* JOHN YEARY OR ITS LICENSORS BE LIABLE FOR ANY LOST REVENUE, PROFIT OR DATA, OR
* FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL, INCIDENTAL OR PUNITIVE
* DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY OF LIABILITY,
* ARISING OUT OF THE USE OF OR INABILITY TO USE SOFTWARE, EVEN IF JOHN YEARY HAS
* BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
*
* You acknowledge that Software is not designed, licensed or intended
* for use in the design, construction, operation or maintenance of any
* nuclear facility.
*/
package net.javanetwork.net;
/**
*
* @author John Yeary
* @version $Revision$
*
* <p>
* This class is designed to transfer files via FTP using the org.apache.commons.net framework.</p>
*/
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.SocketException;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.PatternSyntaxException;
import lombok.Data;
import lombok.NoArgsConstructor;
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;
@NoArgsConstructor
@Data
public class FTPTransfer {
private FTPClient ftp;
private static final Logger log = Logger.getLogger(FTPTransfer.class.getCanonicalName());
/**
* The username to use to login to FTP server.
*/
private String username;
/**
* The target FTP server hostname.
*/
private String hostname;
/**
* Password for username.
*/
private String password;
/**
* The target directory for where the files are to be placed.
*/
private String targetDirectory;
/**
* File transfer type. It is usually {@link FTP#ASCII_FILE_TYPE}, or {@link FTP#BINARY_FILE_TYPE}. The default file
* transfer type is ASCII.
*/
private int fileType = FTP.ASCII_FILE_TYPE;
/**
* Logging level. The default logging level is INFO.
*/
private Level logLevel = Level.INFO;
/**
* An array of files to be transferred.
*/
private java.io.File[] files;
/**
* Indicates if the directory should be created on the remote FTP server if they do not exist.
*/
private boolean createDirectories;
/**
* Connect to FTP server based on the hostname, username, and password set. If it encounters any issues connecting,
* it will call the <code>disconnect()</code> method. This method also starts the default logging.
*/
private void connect() {
int replyCode;
ftp = new FTPClient();
try {
if (hostname != null) {
log.log(Level.INFO, "Connecting to {0}.", hostname);
ftp.connect(hostname);
log.log(Level.INFO, "User: {0}", username);
ftp.login(username, password);
log.log(Level.INFO, ftp.getReplyString());
// Check to make sure we have a usable connection
replyCode = ftp.getReplyCode();
if (!FTPReply.isPositiveCompletion(replyCode)) {
log.log(Level.SEVERE, "FTP failed to connect with reply code: {0}", replyCode);
disconnect();
}
} else {
log.log(Level.SEVERE, "No hostname set. Exiting application.");
System.exit(1);
}
} catch (SocketException e) {
log.log(Level.SEVERE, "SocketException on Connection");
log.log(Level.SEVERE, e.getMessage());
} catch (IOException e) {
log.log(Level.SEVERE, "IOException on Connection");
log.log(Level.SEVERE, e.getMessage());
}
}
/**
* Disconnect from connected FTP server.
*/
private void disconnect() {
try {
log.log(Level.INFO, "Logging out.");
ftp.logout();
} catch (IOException ignored) {
} finally {
try {
if (ftp.isConnected()) {
log.log(Level.INFO, "Disconnecting.");
ftp.disconnect();
log.log(Level.INFO, "Disconnected.");
}
} catch (IOException e) {
log.log(Level.WARNING, "IOException on disconnect.");
log.log(Level.WARNING, e.getMessage());
}
}
}
/**
* Transfers a single file in ASCII or BINARY depending on the file type set using <code>setFileType</code>. The
* default file transfer type is ASCII.
*
* @return
*/
public boolean transferFiles() {
int reply = 0;
FileInputStream in;
String[] targetDirectorySplit;
// Connect to server.
connect();
// Check to see if we are connected before continuing
if (ftp.isConnected()) {
try {
// Change to the requested directory
reply = ftp.cwd(targetDirectory);
log.log(Level.INFO, ftp.getReplyString());
if (FTPReply.isNegativePermanent(reply) && reply == FTPReply.CODE_553) {
// Permission denied to target directory
log.log(Level.SEVERE, "{0} - Permission denied to target directory.", ftp.getReplyString());
} else if (FTPReply.isNegativePermanent(reply) && reply == FTPReply.CODE_550) {
log.log(Level.INFO, "Directory: {0} does not not exist.", targetDirectory);
if (createDirectories) {
log.log(Level.INFO, "Attempting to create {0}.", targetDirectory);
//Split the target directory into tokens to create the directory and sub-directories
targetDirectorySplit = targetDirectory.split("/");
//Create the directory and sub-directories
for (String directory : targetDirectorySplit) {
log.log(Level.INFO, "Creating: {0}", directory);
reply = ftp.mkd(directory);
ftp.cwd(directory);
log.log(Level.INFO, ftp.getReplyString());
}
// Check the final response from server to decide if we should continue.
if (FTPReply.isNegativePermanent(reply)) {
disconnect();
return false;
}
} else {
log.log(Level.SEVERE, "Directory: {0} does not not exist, and the application is not set to create directories.", targetDirectory);
disconnect();
return false;
}
}
} catch (PatternSyntaxException e) {
log.log(Level.SEVERE,
"The target directory format was not in typical UNIX style: /directory/subdirectory");
} catch (IOException e) {
log.log(Level.SEVERE, "Can not create directory {0}.", targetDirectory);
log.log(Level.SEVERE, ftp.getReplyString());
log.log(Level.SEVERE, e.getMessage());
}
}
try {
// Set the file type for data transfer
ftp.setFileType(fileType);
log.log(Level.INFO, ftp.getReplyString());
//Start transferring the files.
for (File file : files) {
if (file != null) {
log.log(Level.INFO, "Opening FileInputStream to: {0}", file.getName());
in = new FileInputStream(file);
log.log(Level.INFO, "Transferring {0} to server.", file.getName());
ftp.storeFile(file.getName(), in);
reply = ftp.getReplyCode();
log.log(Level.INFO, ftp.getReplyString());
// close the FileInputStream
in.close();
log.log(Level.INFO, "FileInputStream closed.");
}
}
} catch (FTPConnectionClosedException e) {
log.log(Level.SEVERE, e.getMessage());
} catch (FileNotFoundException e) {
log.log(Level.SEVERE, e.getMessage());
} catch (IOException e) {
log.log(Level.SEVERE, e.getMessage());
} finally {
try {
if (ftp.isConnected()) {
log.log(Level.INFO, "Disconnecting.");
ftp.disconnect();
log.log(Level.INFO, "Disconnected.");
}
} catch (IOException e) {
log.log(Level.WARNING, "IOException on disconnect.");
log.log(Level.WARNING, e.getMessage());
}
}
return reply == 226;
}
}
Here is an example of how to use it.
package net.javanetwork.net;
import java.io.File;
import lombok.NoArgsConstructor;
import org.apache.commons.net.ftp.FTP;
@NoArgsConstructor
public class FTPExample {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
FTPTransfer ft = new FTPTransfer();
File[] nf = new File[1];
nf[0] = new File("java.png");
ft.setFiles(nf);
ft.setFileType(FTP.BINARY_FILE_TYPE); // The Default is FTP.ASCII
ft.setHostname("speedtest.tele2.net");
ft.setUsername("anonymous");
ft.setPassword("anonymous");
ft.setTargetDirectory("/upload");
System.out.println(ft.transferFiles());
}
}
It is interesting that this code is originally from 2004. The FTP host http://speedtest.tele2.net allows anonymous connections for testing upload and download speeds. A great feature is that it has downloadable files of various sizes for testing.