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how to use SSH in Java to return the result of command input of ubuntu's shell script to java [duplicate]

I am using a JSCH -SSH library to execute command in "shell" channel, but unable to find a way
to do 2 things:-
1) How to find whether the command is completely executed on remote unix box ?
2) How to capture the command output in String , instead of printing it on System.out console ?
Below is my code snippet which works fine to display shell command output on system.out
NOTE :I do NOT want to use ,"exec" channel, as it starts a new process for each command and does not remember "session" variables which were exported. I must use "shell" channel.
Below is my code snippet. Any help is appreciated.Thanks for your time.
try{
String commandToRun = "ls /tmp/*.log \n";
if(channel.isClosed())
channel=session.openChannel("shell");
byte[] bytes = commandToRun.getBytes();
ByteArrayInputStream bais=new ByteArrayInputStream(bytes);
channel.setInputStream(bais);
InputStream ins=channel.getInputStream();
channel.connect();
channel.setOutputStream(System.out);//This prints on console. Need 2 capture in String somehow?
//in-efficient way to allow command to execute completely on remote Unix machine
//DO NOT know a better way, to know when command is executed completely
Thread.sleep(5000L);
}
catch(Exception e){
System.out.println("Exception in executeCommand() --->"+ e.getMessage());
e.printStackTrace();
}

My solution may not be needed anymore for the OP, but anyone else who is searching for a solution to cover both conditions 1) waiting for the commands to finish on remote machine; and 2) capturing output as string; you can try this:
public class SshConnectionManager {
private static Session session;
private static ChannelShell channel;
private static String username = "";
private static String password = "";
private static String hostname = "";
private static Session getSession(){
if(session == null || !session.isConnected()){
session = connect(hostname,username,password);
}
return session;
}
private static Channel getChannel(){
if(channel == null || !channel.isConnected()){
try{
channel = (ChannelShell)getSession().openChannel("shell");
channel.connect();
}catch(Exception e){
System.out.println("Error while opening channel: "+ e);
}
}
return channel;
}
private static Session connect(String hostname, String username, String password){
JSch jSch = new JSch();
try {
session = jSch.getSession(username, hostname, 22);
Properties config = new Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
session.setPassword(password);
System.out.println("Connecting SSH to " + hostname + " - Please wait for few seconds... ");
session.connect();
System.out.println("Connected!");
}catch(Exception e){
System.out.println("An error occurred while connecting to "+hostname+": "+e);
}
return session;
}
private static void executeCommands(List<String> commands){
try{
Channel channel=getChannel();
System.out.println("Sending commands...");
sendCommands(channel, commands);
readChannelOutput(channel);
System.out.println("Finished sending commands!");
}catch(Exception e){
System.out.println("An error ocurred during executeCommands: "+e);
}
}
private static void sendCommands(Channel channel, List<String> commands){
try{
PrintStream out = new PrintStream(channel.getOutputStream());
out.println("#!/bin/bash");
for(String command : commands){
out.println(command);
}
out.println("exit");
out.flush();
}catch(Exception e){
System.out.println("Error while sending commands: "+ e);
}
}
private static void readChannelOutput(Channel channel){
byte[] buffer = new byte[1024];
try{
InputStream in = channel.getInputStream();
String line = "";
while (true){
while (in.available() > 0) {
int i = in.read(buffer, 0, 1024);
if (i < 0) {
break;
}
line = new String(buffer, 0, i);
System.out.println(line);
}
if(line.contains("logout")){
break;
}
if (channel.isClosed()){
break;
}
try {
Thread.sleep(1000);
} catch (Exception ee){}
}
}catch(Exception e){
System.out.println("Error while reading channel output: "+ e);
}
}
public static void close(){
channel.disconnect();
session.disconnect();
System.out.println("Disconnected channel and session");
}
public static void main(String[] args){
List<String> commands = new ArrayList<String>();
commands.add("ls -l");
executeCommands(commands);
close();
}
}
This solution is also useful if you need to send multiple commands at a time and keep the channel open to reuse it later.

For 2) u can use ByteArrayOutputStream
final ByteArrayOutputStream baos = new ByteArrayOutputStream();
channel.setOutputStream(baos);
and then create new string from new String(baos.toByteArray())
For 1 have you tried to use 2>&1 at the end of your command?
String commandToRun = "ls /tmp/*.log 2>&1 \n";

Taking the example provided by Mihail, other info on the internets, and the feedback from Martin, here's a reworked solution using exec. Note that opening a session allows multiple commands to be sent, each one opening it's own channel for input/output.
Rant:I really dislike having to get the process' OUTPUT stream to write to. What an annoying paradigm (at least for me). What I wanted is the processes input stream to write my output to, and had an amazingly difficult time working out that it's inverted. Is it just me or does the following (pseudocode) not make way more sense??
channel.getInputStream().write("here's some text to write into my channel.");
String ret = channel.getOutputStream().getOutput();
Anyways, thanks to Mihail and Martin for their comments / input.
public class SSHConnectionManager {
private Session session;
private String username = "user";
private String password = "password";
private String hostname = "myhost";
public SSHConnectionManager() { }
public SSHConnectionManager(String hostname, String username, String password) {
this.hostname = hostname;
this.username = username;
this.password = password;
}
public void open() throws JSchException {
open(this.hostname, this.username, this.password);
}
public void open(String hostname, String username, String password) throws JSchException{
JSch jSch = new JSch();
session = jSch.getSession(username, hostname, 22);
Properties config = new Properties();
config.put("StrictHostKeyChecking", "no"); // not recommended
session.setConfig(config);
session.setPassword(password);
System.out.println("Connecting SSH to " + hostname + " - Please wait for few seconds... ");
session.connect();
System.out.println("Connected!");
}
public String runCommand(String command) throws JSchException, IOException {
String ret = "";
if (!session.isConnected())
throw new RuntimeException("Not connected to an open session. Call open() first!");
ChannelExec channel = null;
channel = (ChannelExec) session.openChannel("exec");
channel.setCommand(command);
channel.setInputStream(null);
PrintStream out = new PrintStream(channel.getOutputStream());
InputStream in = channel.getInputStream(); // channel.getInputStream();
channel.connect();
// you can also send input to your running process like so:
// String someInputToProcess = "something";
// out.println(someInputToProcess);
// out.flush();
ret = getChannelOutput(channel, in);
channel.disconnect();
System.out.println("Finished sending commands!");
return ret;
}
private String getChannelOutput(Channel channel, InputStream in) throws IOException{
byte[] buffer = new byte[1024];
StringBuilder strBuilder = new StringBuilder();
String line = "";
while (true){
while (in.available() > 0) {
int i = in.read(buffer, 0, 1024);
if (i < 0) {
break;
}
strBuilder.append(new String(buffer, 0, i));
System.out.println(line);
}
if(line.contains("logout")){
break;
}
if (channel.isClosed()){
break;
}
try {
Thread.sleep(1000);
} catch (Exception ee){}
}
return strBuilder.toString();
}
public void close(){
session.disconnect();
System.out.println("Disconnected channel and session");
}
public static void main(String[] args){
SSHConnectionManager ssh = new SSHConnectionManager();
try {
ssh.open();
String ret = ssh.runCommand("ls -l");
System.out.println(ret);
ssh.close();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}

download file from SFTP url [duplicate]

I'm trying to retrieve a file from a server using SFTP (as opposed to FTPS) using Java. How can I do this?

Another option is to consider looking at the JSch library. JSch seems to be the preferred library for a few large open source projects, including Eclipse, Ant and Apache Commons HttpClient, amongst others.
It supports both user/pass and certificate-based logins nicely, as well as all a whole host of other yummy SSH2 features.
Here's a simple remote file retrieve over SFTP. Error handling is left as an exercise for the reader :-)
JSch jsch = new JSch();
String knownHostsFilename = "/home/username/.ssh/known_hosts";
jsch.setKnownHosts( knownHostsFilename );
Session session = jsch.getSession( "remote-username", "remote-host" );
{
// "interactive" version
// can selectively update specified known_hosts file
// need to implement UserInfo interface
// MyUserInfo is a swing implementation provided in
// examples/Sftp.java in the JSch dist
UserInfo ui = new MyUserInfo();
session.setUserInfo(ui);
// OR non-interactive version. Relies in host key being in known-hosts file
session.setPassword( "remote-password" );
}
session.connect();
Channel channel = session.openChannel( "sftp" );
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remote-file", "local-file" );
// OR
InputStream in = sftpChannel.get( "remote-file" );
// process inputstream as needed
sftpChannel.exit();
session.disconnect();

Here is the complete source code of an example using JSch without having to worry about the ssh key checking.
import com.jcraft.jsch.*;
public class TestJSch {
public static void main(String args[]) {
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("username", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remotefile.txt", "localfile.txt");
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
}
}

Below is an example using Apache Common VFS:
FileSystemOptions fsOptions = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(fsOptions, "no");
FileSystemManager fsManager = VFS.getManager();
String uri = "sftp://user:password#host:port/absolute-path";
FileObject fo = fsManager.resolveFile(uri, fsOptions);

A nice abstraction on top of Jsch is Apache commons-vfs which offers a virtual filesystem API that makes accessing and writing SFTP files almost transparent. Worked well for us.

This was the solution I came up with
http://sourceforge.net/projects/sshtools/ (most error handling omitted for clarity). This is an excerpt from my blog
SshClient ssh = new SshClient();
ssh.connect(host, port);
//Authenticate
PasswordAuthenticationClient passwordAuthenticationClient = new PasswordAuthenticationClient();
passwordAuthenticationClient.setUsername(userName);
passwordAuthenticationClient.setPassword(password);
int result = ssh.authenticate(passwordAuthenticationClient);
if(result != AuthenticationProtocolState.COMPLETE){
throw new SFTPException("Login to " + host + ":" + port + " " + userName + "/" + password + " failed");
}
//Open the SFTP channel
SftpClient client = ssh.openSftpClient();
//Send the file
client.put(filePath);
//disconnect
client.quit();
ssh.disconnect();

There is a nice comparison of the 3 mature Java libraries for SFTP: Commons VFS, SSHJ and JSch
To sum up SSHJ has the clearest API and it's the best out of them if you don't need other storages support provided by Commons VFS.
Here is edited SSHJ example from github:
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts(); // or, to skip host verification: ssh.addHostKeyVerifier(new PromiscuousVerifier())
ssh.connect("localhost");
try {
ssh.authPassword("user", "password"); // or ssh.authPublickey(System.getProperty("user.name"))
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.get("test_file", "/tmp/test.tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}

See http://www.mysamplecode.com/2013/06/sftp-apache-commons-file-download.html
Apache Commons SFTP library
Common java properties file for all the examples
serverAddress=111.222.333.444
userId=myUserId
password=myPassword
remoteDirectory=products/
localDirectory=import/
Upload file to remote server using SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class SendMyFiles {
static Properties props;
public static void main(String[] args) {
SendMyFiles sendMyFiles = new SendMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + sendMyFiles.getClass().getName()+
" Properties_file File_To_FTP ");
System.exit(1);
}
String propertiesFile = args[0].trim();
String fileToFTP = args[1].trim();
sendMyFiles.startFTP(propertiesFile, fileToFTP);
}
public boolean startFTP(String propertiesFilename, String fileToFTP){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//check if the file exists
String filepath = localDirectory + fileToFTP;
File file = new File(filepath);
if (!file.exists())
throw new RuntimeException("Error. Local file not found");
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "#" + serverAddress + "/" +
remoteDirectory + fileToFTP;
// Create local file object
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
remoteFile.copyFrom(localFile, Selectors.SELECT_SELF);
System.out.println("File upload successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Download file from remote server using SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class GetMyFiles {
static Properties props;
public static void main(String[] args) {
GetMyFiles getMyFiles = new GetMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Download ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "#" + serverAddress + "/" +
remoteDirectory + fileToDownload;
// Create local file object
String filepath = localDirectory + fileToDownload;
File file = new File(filepath);
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
localFile.copyFrom(remoteFile, Selectors.SELECT_SELF);
System.out.println("File download successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Delete a file on remote server using SFTP
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class DeleteRemoteFile {
static Properties props;
public static void main(String[] args) {
DeleteRemoteFile getMyFiles = new DeleteRemoteFile();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Delete ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "#" + serverAddress + "/" +
remoteDirectory + fileToDownload;
//Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
//Check if the file exists
if(remoteFile.exists()){
remoteFile.delete();
System.out.println("File delete successful");
}
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}

hierynomus/sshj has a complete implementation of SFTP version 3 (what OpenSSH implements)
Example code from SFTPUpload.java
package net.schmizz.sshj.examples;
import net.schmizz.sshj.SSHClient;
import net.schmizz.sshj.sftp.SFTPClient;
import net.schmizz.sshj.xfer.FileSystemFile;
import java.io.File;
import java.io.IOException;
/** This example demonstrates uploading of a file over SFTP to the SSH server. */
public class SFTPUpload {
public static void main(String[] args)
throws IOException {
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts();
ssh.connect("localhost");
try {
ssh.authPublickey(System.getProperty("user.name"));
final String src = System.getProperty("user.home") + File.separator + "test_file";
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.put(new FileSystemFile(src), "/tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}
}
}

JSch library is the powerful library that can be used to read file from SFTP server. Below is the tested code to read file from SFTP location line by line
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("user", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
InputStream stream = sftpChannel.get("/usr/home/testfile.txt");
try {
BufferedReader br = new BufferedReader(new InputStreamReader(stream));
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException io) {
System.out.println("Exception occurred during reading file from SFTP server due to " + io.getMessage());
io.getMessage();
} catch (Exception e) {
System.out.println("Exception occurred during reading file from SFTP server due to " + e.getMessage());
e.getMessage();
}
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
Please refer the blog for whole program.

Andy, to delete file on remote system you need to use (channelExec) of JSch and pass unix/linux commands to delete it.

Try edtFTPj/PRO, a mature, robust SFTP client library that supports connection pools and asynchronous operations. Also supports FTP and FTPS so all bases for secure file transfer are covered.

I found complete working example for SFTP in java using JSCH API
http://kodehelp.com/java-program-for-uploading-file-to-sftp-server/

Though answers above were very helpful, I've spent a day to make them work, facing various exceptions like "broken channel", "rsa key unknown" and "packet corrupt".
Below is a working reusable class for SFTP FILES UPLOAD/DOWNLOAD using JSch library.
Upload usage:
SFTPFileCopy upload = new SFTPFileCopy(true, /path/to/sourcefile.png", /path/to/destinationfile.png");
Download usage:
SFTPFileCopy download = new SFTPFileCopy(false, "/path/to/sourcefile.png", "/path/to/destinationfile.png");
The class code:
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UIKeyboardInteractive;
import com.jcraft.jsch.UserInfo;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.swing.JOptionPane;
import menue.Menue;
public class SFTPFileCopy1 {
public SFTPFileCopy1(boolean upload, String sourcePath, String destPath) throws FileNotFoundException, IOException {
Session session = null;
Channel channel = null;
ChannelSftp sftpChannel = null;
try {
JSch jsch = new JSch();
//jsch.setKnownHosts("/home/user/.putty/sshhostkeys");
session = jsch.getSession("login", "mysite.com", 22);
session.setPassword("password");
UserInfo ui = new MyUserInfo() {
public void showMessage(String message) {
JOptionPane.showMessageDialog(null, message);
}
public boolean promptYesNo(String message) {
Object[] options = {"yes", "no"};
int foo = JOptionPane.showOptionDialog(null,
message,
"Warning",
JOptionPane.DEFAULT_OPTION,
JOptionPane.WARNING_MESSAGE,
null, options, options[0]);
return foo == 0;
}
};
session.setUserInfo(ui);
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
channel = session.openChannel("sftp");
channel.setInputStream(System.in);
channel.setOutputStream(System.out);
channel.connect();
sftpChannel = (ChannelSftp) channel;
if (upload) { // File upload.
byte[] bufr = new byte[(int) new File(sourcePath).length()];
FileInputStream fis = new FileInputStream(new File(sourcePath));
fis.read(bufr);
ByteArrayInputStream fileStream = new ByteArrayInputStream(bufr);
sftpChannel.put(fileStream, destPath);
fileStream.close();
} else { // File download.
byte[] buffer = new byte[1024];
BufferedInputStream bis = new BufferedInputStream(sftpChannel.get(sourcePath));
OutputStream os = new FileOutputStream(new File(destPath));
BufferedOutputStream bos = new BufferedOutputStream(os);
int readCount;
while ((readCount = bis.read(buffer)) > 0) {
bos.write(buffer, 0, readCount);
}
bis.close();
bos.close();
}
} catch (Exception e) {
System.out.println(e);
} finally {
if (sftpChannel != null) {
sftpChannel.exit();
}
if (channel != null) {
channel.disconnect();
}
if (session != null) {
session.disconnect();
}
}
}
public static abstract class MyUserInfo
implements UserInfo, UIKeyboardInteractive {
public String getPassword() {
return null;
}
public boolean promptYesNo(String str) {
return false;
}
public String getPassphrase() {
return null;
}
public boolean promptPassphrase(String message) {
return false;
}
public boolean promptPassword(String message) {
return false;
}
public void showMessage(String message) {
}
public String[] promptKeyboardInteractive(String destination,
String name,
String instruction,
String[] prompt,
boolean[] echo) {
return null;
}
}
}

You also have JFileUpload with SFTP add-on (Java too):
http://www.jfileupload.com/products/sftp/index.html

I use this SFTP API called Zehon, it's great, so easy to use with a lot of sample code. Here is the site http://www.zehon.com

The best solution I've found is Paramiko. There's a Java version.

JSCH Console Read Showing Same Output for Different Commands

I am trying to send some commands to a router and trying to read the console output. But the problem is every time i send a new command i get the same output. I tried creating a new session after every command is executed but I still get the same output. I got a sample online and modified it according to my needs. When i run it as a standalone class, it works perfectly. But when deployed on a server, it just doesn't seem to work right. To be honest, I am only its only been a day or two I have used the JSCH and documentation is very sparse.
This is how my code reads:
private void writeCommand(String command) throws IOException, JSchException {
Channel channel = getChannel();
((ChannelExec) channel).setCommand(command.getBytes());
channel.setInputStream(null);
((ChannelExec) channel).setErrStream(System.err);
readChannelOutput(channel);
}
private void readChannelOutput(Channel channel) {
byte[] buffer = new byte[1024];
try {
InputStream inputStream = channel.getInputStream();
channel.connect();
while (true) {
while (inputStream.available() > 0) {
int i = inputStream.read(buffer, 0, 1024);
if (i < 0) {
break;
}
deviceOut.updateDeviceOutput(new String(buffer, 0, i));
}
if (channel.isClosed()) {
break;
}
}
disconnect();
} catch(IOException e) {
e.printstacktrace();
} catch (JSchException e) {
e.printstacktrace();
}
}
public Session getSession () throws Exception {
if (session == null || !session.isConnected()) {
session = connect(getUserid(), getIpaddress(), getPassword(), getPort());
}
return session;
}
protected Session connect(String userName, String hostname, String password, int port) throws Exception {
JSch jSch = new JSch();
try {
session = jSch.getSession(userName, hostname, port);
Properties config = new Properties();
config.put("StrictHostKeyChecking", "no");
session.setConfig(config);
session.setPassword(password);
logger.debug("Connecting SSH to " + getIpaddress() + " - Please wait for few seconds... ");
session.connect();
logger.debug("Connected!");
if (session.isConnected()) {
setConnectionState(DeviceConnection.LOGIN_COMPLETE);
} else {
setConnectionState(DeviceConnection.LOGIN_FAILED);
throw new Exception("Failed to login to device");
}
deviceOut = new DeviceOutput(getLogger());
return session;
} catch (JSchException e) {
disconnect();
e.printstacktrace();
} catch (PalException e) {
disconnect();
e.printstacktrace();
}
}
The commands that I am trying to send are
term len 512
and
show running-config | include hostname
But the output just stays the same. The first command should not even have any ouput to be honest. Is there anything I am doing wrong?

Java - Kerberos authentication linux

I am trying to connect Linux from windows using Java. Given below is the code which I have used for this process. The actual issue I am facing during session.connect() .i.e. it is prompting for Kerberos username which I have tried to enter username and password using command exec but I am not able to succeed.
I cannot skip Kerberos authentication also since this authentication is required to perform any batch operations.
Please assist me in connecting Linux by entering Kerberos username and password in an automated way.
Java code:
import com.jcraft.jsch.*;
import java.io.BufferedReader;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
public class SSHClient {
public static void main(String[] args) throws JSchException, IOException {
String endLineStr = " # "; // it is dependant to the server
String host = ""; // host IP
String user = ""; // username for SSH connection
String password = ""; // password for SSH connection
int port = 22; // default SSH port
JSch shell = new JSch();
// get a new session
Session session = shell.getSession(user, host, port);
// set user password and connect to a channel
session.setUserInfo(new SSHUserInfo(password));
session.connect();
Channel channel = session.openChannel("shell");
channel.connect();
ChannelExec channelExec = (ChannelExec)session.openChannel("exec");
InputStream in = channelExec.getInputStream();
channelExec.setCommand("ls");
channelExec.connect();
BufferedReader reader = new BufferedReader(new InputStreamReader(in));
String line;
int index = 0;
while ((line = reader.readLine()) != null)
{
System.out.println(++index + " : " + line);
}
int exitStatus = channelExec.getExitStatus();
channelExec.disconnect();
session.disconnect();
if(exitStatus < 0){
System.out.println("Done, but exit status not set!");
}
else if(exitStatus > 0){
System.out.println("Done, but with error!");
}
else{
System.out.println("Done!");
}
// DataInputStream dataIn = new DataInputStream(channel.getInputStream());
// DataOutputStream dataOut = new DataOutputStream(channel.getOutputStream());
//
// // send ls command to the server
// dataOut.writeBytes("ls");
// dataOut.flush();
//
// // and print the response
// String line = dataIn.readLine();
// System.out.println(line);
// while(!line.endsWith(endLineStr)) {
// System.out.println(line);
// line = dataIn.readLine();
// }
// dataIn.close();
// dataOut.close();
channel.disconnect();
session.disconnect();
}
// this class implements jsch UserInfo interface for passing password to the session
static class SSHUserInfo implements UserInfo {
private String password;
SSHUserInfo(String password) {
this.password = password;
}
public String getPassphrase() {
return null;
}
public String getPassword() {
return password;
}
public boolean promptPassword(String arg0) {
return true;
}
public boolean promptPassphrase(String arg0) {
return true;
}
public boolean promptYesNo(String arg0) {
return true;
}
public void showMessage(String arg0) {
System.out.println(arg0);
}
}
}

How to retrieve a file from a server via SFTP?

I'm trying to retrieve a file from a server using SFTP (as opposed to FTPS) using Java. How can I do this?

Another option is to consider looking at the JSch library. JSch seems to be the preferred library for a few large open source projects, including Eclipse, Ant and Apache Commons HttpClient, amongst others.
It supports both user/pass and certificate-based logins nicely, as well as all a whole host of other yummy SSH2 features.
Here's a simple remote file retrieve over SFTP. Error handling is left as an exercise for the reader :-)
JSch jsch = new JSch();
String knownHostsFilename = "/home/username/.ssh/known_hosts";
jsch.setKnownHosts( knownHostsFilename );
Session session = jsch.getSession( "remote-username", "remote-host" );
{
// "interactive" version
// can selectively update specified known_hosts file
// need to implement UserInfo interface
// MyUserInfo is a swing implementation provided in
// examples/Sftp.java in the JSch dist
UserInfo ui = new MyUserInfo();
session.setUserInfo(ui);
// OR non-interactive version. Relies in host key being in known-hosts file
session.setPassword( "remote-password" );
}
session.connect();
Channel channel = session.openChannel( "sftp" );
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remote-file", "local-file" );
// OR
InputStream in = sftpChannel.get( "remote-file" );
// process inputstream as needed
sftpChannel.exit();
session.disconnect();

Here is the complete source code of an example using JSch without having to worry about the ssh key checking.
import com.jcraft.jsch.*;
public class TestJSch {
public static void main(String args[]) {
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("username", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
sftpChannel.get("remotefile.txt", "localfile.txt");
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
}
}

Below is an example using Apache Common VFS:
FileSystemOptions fsOptions = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(fsOptions, "no");
FileSystemManager fsManager = VFS.getManager();
String uri = "sftp://user:password#host:port/absolute-path";
FileObject fo = fsManager.resolveFile(uri, fsOptions);

A nice abstraction on top of Jsch is Apache commons-vfs which offers a virtual filesystem API that makes accessing and writing SFTP files almost transparent. Worked well for us.

This was the solution I came up with
http://sourceforge.net/projects/sshtools/ (most error handling omitted for clarity). This is an excerpt from my blog
SshClient ssh = new SshClient();
ssh.connect(host, port);
//Authenticate
PasswordAuthenticationClient passwordAuthenticationClient = new PasswordAuthenticationClient();
passwordAuthenticationClient.setUsername(userName);
passwordAuthenticationClient.setPassword(password);
int result = ssh.authenticate(passwordAuthenticationClient);
if(result != AuthenticationProtocolState.COMPLETE){
throw new SFTPException("Login to " + host + ":" + port + " " + userName + "/" + password + " failed");
}
//Open the SFTP channel
SftpClient client = ssh.openSftpClient();
//Send the file
client.put(filePath);
//disconnect
client.quit();
ssh.disconnect();

There is a nice comparison of the 3 mature Java libraries for SFTP: Commons VFS, SSHJ and JSch
To sum up SSHJ has the clearest API and it's the best out of them if you don't need other storages support provided by Commons VFS.
Here is edited SSHJ example from github:
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts(); // or, to skip host verification: ssh.addHostKeyVerifier(new PromiscuousVerifier())
ssh.connect("localhost");
try {
ssh.authPassword("user", "password"); // or ssh.authPublickey(System.getProperty("user.name"))
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.get("test_file", "/tmp/test.tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}

See http://www.mysamplecode.com/2013/06/sftp-apache-commons-file-download.html
Apache Commons SFTP library
Common java properties file for all the examples
serverAddress=111.222.333.444
userId=myUserId
password=myPassword
remoteDirectory=products/
localDirectory=import/
Upload file to remote server using SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class SendMyFiles {
static Properties props;
public static void main(String[] args) {
SendMyFiles sendMyFiles = new SendMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + sendMyFiles.getClass().getName()+
" Properties_file File_To_FTP ");
System.exit(1);
}
String propertiesFile = args[0].trim();
String fileToFTP = args[1].trim();
sendMyFiles.startFTP(propertiesFile, fileToFTP);
}
public boolean startFTP(String propertiesFilename, String fileToFTP){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//check if the file exists
String filepath = localDirectory + fileToFTP;
File file = new File(filepath);
if (!file.exists())
throw new RuntimeException("Error. Local file not found");
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "#" + serverAddress + "/" +
remoteDirectory + fileToFTP;
// Create local file object
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
remoteFile.copyFrom(localFile, Selectors.SELECT_SELF);
System.out.println("File upload successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Download file from remote server using SFTP
import java.io.File;
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.Selectors;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class GetMyFiles {
static Properties props;
public static void main(String[] args) {
GetMyFiles getMyFiles = new GetMyFiles();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Download ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
String localDirectory = props.getProperty("localDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "#" + serverAddress + "/" +
remoteDirectory + fileToDownload;
// Create local file object
String filepath = localDirectory + fileToDownload;
File file = new File(filepath);
FileObject localFile = manager.resolveFile(file.getAbsolutePath());
// Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
// Copy local file to sftp server
localFile.copyFrom(remoteFile, Selectors.SELECT_SELF);
System.out.println("File download successful");
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}
Delete a file on remote server using SFTP
import java.io.FileInputStream;
import java.util.Properties;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemOptions;
import org.apache.commons.vfs2.impl.StandardFileSystemManager;
import org.apache.commons.vfs2.provider.sftp.SftpFileSystemConfigBuilder;
public class DeleteRemoteFile {
static Properties props;
public static void main(String[] args) {
DeleteRemoteFile getMyFiles = new DeleteRemoteFile();
if (args.length < 1)
{
System.err.println("Usage: java " + getMyFiles.getClass().getName()+
" Properties_filename File_To_Delete ");
System.exit(1);
}
String propertiesFilename = args[0].trim();
String fileToDownload = args[1].trim();
getMyFiles.startFTP(propertiesFilename, fileToDownload);
}
public boolean startFTP(String propertiesFilename, String fileToDownload){
props = new Properties();
StandardFileSystemManager manager = new StandardFileSystemManager();
try {
props.load(new FileInputStream("properties/" + propertiesFilename));
String serverAddress = props.getProperty("serverAddress").trim();
String userId = props.getProperty("userId").trim();
String password = props.getProperty("password").trim();
String remoteDirectory = props.getProperty("remoteDirectory").trim();
//Initializes the file manager
manager.init();
//Setup our SFTP configuration
FileSystemOptions opts = new FileSystemOptions();
SftpFileSystemConfigBuilder.getInstance().setStrictHostKeyChecking(
opts, "no");
SftpFileSystemConfigBuilder.getInstance().setUserDirIsRoot(opts, true);
SftpFileSystemConfigBuilder.getInstance().setTimeout(opts, 10000);
//Create the SFTP URI using the host name, userid, password, remote path and file name
String sftpUri = "sftp://" + userId + ":" + password + "#" + serverAddress + "/" +
remoteDirectory + fileToDownload;
//Create remote file object
FileObject remoteFile = manager.resolveFile(sftpUri, opts);
//Check if the file exists
if(remoteFile.exists()){
remoteFile.delete();
System.out.println("File delete successful");
}
}
catch (Exception ex) {
ex.printStackTrace();
return false;
}
finally {
manager.close();
}
return true;
}
}

hierynomus/sshj has a complete implementation of SFTP version 3 (what OpenSSH implements)
Example code from SFTPUpload.java
package net.schmizz.sshj.examples;
import net.schmizz.sshj.SSHClient;
import net.schmizz.sshj.sftp.SFTPClient;
import net.schmizz.sshj.xfer.FileSystemFile;
import java.io.File;
import java.io.IOException;
/** This example demonstrates uploading of a file over SFTP to the SSH server. */
public class SFTPUpload {
public static void main(String[] args)
throws IOException {
final SSHClient ssh = new SSHClient();
ssh.loadKnownHosts();
ssh.connect("localhost");
try {
ssh.authPublickey(System.getProperty("user.name"));
final String src = System.getProperty("user.home") + File.separator + "test_file";
final SFTPClient sftp = ssh.newSFTPClient();
try {
sftp.put(new FileSystemFile(src), "/tmp");
} finally {
sftp.close();
}
} finally {
ssh.disconnect();
}
}
}

JSch library is the powerful library that can be used to read file from SFTP server. Below is the tested code to read file from SFTP location line by line
JSch jsch = new JSch();
Session session = null;
try {
session = jsch.getSession("user", "127.0.0.1", 22);
session.setConfig("StrictHostKeyChecking", "no");
session.setPassword("password");
session.connect();
Channel channel = session.openChannel("sftp");
channel.connect();
ChannelSftp sftpChannel = (ChannelSftp) channel;
InputStream stream = sftpChannel.get("/usr/home/testfile.txt");
try {
BufferedReader br = new BufferedReader(new InputStreamReader(stream));
String line;
while ((line = br.readLine()) != null) {
System.out.println(line);
}
} catch (IOException io) {
System.out.println("Exception occurred during reading file from SFTP server due to " + io.getMessage());
io.getMessage();
} catch (Exception e) {
System.out.println("Exception occurred during reading file from SFTP server due to " + e.getMessage());
e.getMessage();
}
sftpChannel.exit();
session.disconnect();
} catch (JSchException e) {
e.printStackTrace();
} catch (SftpException e) {
e.printStackTrace();
}
Please refer the blog for whole program.

Andy, to delete file on remote system you need to use (channelExec) of JSch and pass unix/linux commands to delete it.

Try edtFTPj/PRO, a mature, robust SFTP client library that supports connection pools and asynchronous operations. Also supports FTP and FTPS so all bases for secure file transfer are covered.

I found complete working example for SFTP in java using JSCH API
http://kodehelp.com/java-program-for-uploading-file-to-sftp-server/

Though answers above were very helpful, I've spent a day to make them work, facing various exceptions like "broken channel", "rsa key unknown" and "packet corrupt".
Below is a working reusable class for SFTP FILES UPLOAD/DOWNLOAD using JSch library.
Upload usage:
SFTPFileCopy upload = new SFTPFileCopy(true, /path/to/sourcefile.png", /path/to/destinationfile.png");
Download usage:
SFTPFileCopy download = new SFTPFileCopy(false, "/path/to/sourcefile.png", "/path/to/destinationfile.png");
The class code:
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.UIKeyboardInteractive;
import com.jcraft.jsch.UserInfo;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import javax.swing.JOptionPane;
import menue.Menue;
public class SFTPFileCopy1 {
public SFTPFileCopy1(boolean upload, String sourcePath, String destPath) throws FileNotFoundException, IOException {
Session session = null;
Channel channel = null;
ChannelSftp sftpChannel = null;
try {
JSch jsch = new JSch();
//jsch.setKnownHosts("/home/user/.putty/sshhostkeys");
session = jsch.getSession("login", "mysite.com", 22);
session.setPassword("password");
UserInfo ui = new MyUserInfo() {
public void showMessage(String message) {
JOptionPane.showMessageDialog(null, message);
}
public boolean promptYesNo(String message) {
Object[] options = {"yes", "no"};
int foo = JOptionPane.showOptionDialog(null,
message,
"Warning",
JOptionPane.DEFAULT_OPTION,
JOptionPane.WARNING_MESSAGE,
null, options, options[0]);
return foo == 0;
}
};
session.setUserInfo(ui);
session.setConfig("StrictHostKeyChecking", "no");
session.connect();
channel = session.openChannel("sftp");
channel.setInputStream(System.in);
channel.setOutputStream(System.out);
channel.connect();
sftpChannel = (ChannelSftp) channel;
if (upload) { // File upload.
byte[] bufr = new byte[(int) new File(sourcePath).length()];
FileInputStream fis = new FileInputStream(new File(sourcePath));
fis.read(bufr);
ByteArrayInputStream fileStream = new ByteArrayInputStream(bufr);
sftpChannel.put(fileStream, destPath);
fileStream.close();
} else { // File download.
byte[] buffer = new byte[1024];
BufferedInputStream bis = new BufferedInputStream(sftpChannel.get(sourcePath));
OutputStream os = new FileOutputStream(new File(destPath));
BufferedOutputStream bos = new BufferedOutputStream(os);
int readCount;
while ((readCount = bis.read(buffer)) > 0) {
bos.write(buffer, 0, readCount);
}
bis.close();
bos.close();
}
} catch (Exception e) {
System.out.println(e);
} finally {
if (sftpChannel != null) {
sftpChannel.exit();
}
if (channel != null) {
channel.disconnect();
}
if (session != null) {
session.disconnect();
}
}
}
public static abstract class MyUserInfo
implements UserInfo, UIKeyboardInteractive {
public String getPassword() {
return null;
}
public boolean promptYesNo(String str) {
return false;
}
public String getPassphrase() {
return null;
}
public boolean promptPassphrase(String message) {
return false;
}
public boolean promptPassword(String message) {
return false;
}
public void showMessage(String message) {
}
public String[] promptKeyboardInteractive(String destination,
String name,
String instruction,
String[] prompt,
boolean[] echo) {
return null;
}
}
}

You also have JFileUpload with SFTP add-on (Java too):
http://www.jfileupload.com/products/sftp/index.html

I use this SFTP API called Zehon, it's great, so easy to use with a lot of sample code. Here is the site http://www.zehon.com

The best solution I've found is Paramiko. There's a Java version.