如何通过SFTP从服务器检索文件?

我试图使用Java使用SFTP(而不是FTPS)从服务器检索一个文件。我该怎么做呢?

430313 次浏览
小开
这是我想到的解决办法 http://sourceforge.net/projects/sshtools/(为了清晰起见，省略了大多数错误处理)。这是我的博客

的节选 
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();
小开
最佳答案

另一个选择是考虑查看JSch图书馆。JSch似乎是一些大型开源项目的首选库，包括Eclipse、Ant和Apache Commons HttpClient等等。

它很好地支持用户/通行证和基于证书的登录，以及所有其他漂亮的SSH2特性。

这是一个简单的远程文件检索SFTP。错误处理留给读者练习:-)

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();
小开

在Jsch之上的一个很好的抽象是Apache commons-vfs，它提供了一个虚拟文件系统API，使得访问和写入SFTP文件几乎是透明的。这对我们来说很有效。

小开

我找到的最佳解决方案是Paramiko。有一个Java版本。

小开
你也有JFileUpload SFTP插件(Java也): http://www.jfileupload.com/products/sftp/index.html < / p >
小开

尝试edtFTPj /职业，一个成熟的，健壮的SFTP客户端库，支持连接池和异步操作。还支持FTP和FTPS，因此安全文件传输的所有基础都包括在内。

小开

我使用这个叫做Zehon的SFTP API，它很棒，很容易使用，有很多示例代码。这里是站点http://www.zehon.com

小开

hierynomus / sshj有一个完整的SFTP版本3的实现(OpenSSH实现的)

来自SFTPUpload.java的示例代码

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();
}
}


}
小开

下面是一个使用Apache Common VFS的例子:

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);
小开

下面是一个使用JSch的示例的完整源代码，而不必担心ssh密钥检查。

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();
}
}
}
小开
我在java中使用JSCH API找到了完整的SFTP工作示例 http://kodehelp.com/java-program-for-uploading-file-to-sftp-server/ < / p >
小开

安迪，要在远程系统上删除文件，你需要使用JSch的(channelExec)，并传递unix/linux命令来删除它。

小开

虽然上面的答案很有帮助，但我花了一天时间让它们工作，面对各种异常，如“中断通道”，“rsa密钥未知”和“数据包损坏”。

下面是一个工作的可重用类SFTP文件上传/下载使用JSch库。

上传用法:

SFTPFileCopy upload = new SFTPFileCopy(true, /path/to/sourcefile.png", /path/to/destinationfile.png");

下载使用:

SFTPFileCopy download = new SFTPFileCopy(false, "/path/to/sourcefile.png", "/path/to/destinationfile.png");

类代码:

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;
}
}
}
小开

看到http://www.mysamplecode.com/2013/06/sftp-apache-commons-file-download.html

Apache Commons SFTP库

所有示例的公共java属性文件

serverAddress = 111.222.333.444

用户id = myUserId

密码=我的密码

remoteDirectory =产品/

localDirectory =进口/

使用SFTP上传文件到远程服务器

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;
}
 

  

}

使用SFTP从远程服务器下载文件

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;
}
 

}

使用SFTP删除远程服务器上的文件

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;
}
 

}
小开

有一个比较SFTP的3个成熟Java库:通用VFS, SSHJ和JSch

总而言之，如果你不需要Commons VFS提供的其他存储支持，那么SSHJ具有最清晰的API，是其中最好的API。

下面是来自github的经过编辑的SSHJ示例:

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();
}
小开

JSch库是一个功能强大的库，可以用来从SFTP服务器读取文件。下面是逐行从SFTP位置读取文件的测试代码

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();
}

整个程序请参考博客。


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