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?


当前回答

你也有JFileUpload SFTP插件(Java也是): http://www.jfileupload.com/products/sftp/index.html

其他回答

这就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();

另一种选择是考虑查看JSch库。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();

有3个成熟的用于SFTP的Java库:Commons 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。

下面是从github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();
}

下面是使用JSch的示例的完整源代码,无需担心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();
        }
    }
}

我找到的最好的解决办法是帕拉米科。有一个Java版本。