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

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。

其他回答

我找到的最好的解决办法是帕拉米科。有一个Java版本。

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();

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);

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。

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;
        }
    }
}