（曾在天涯）的文章详细讲解了jsch中的函数以及用法

http://www.cnblogs.com/longyg/archive/2012/06/25/2556576.html

http://www.cnblogs.com/longyg/archive/2012/06/25/2561332.html

下面是一个例子：

package com.util;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.Properties;
import java.util.Vector;
import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.SftpException;
import com.jcraft.jsch.ChannelSftp.LsEntry;

public class Jsch4Sftp {
 /**
  * 连接sftp服务器
  * 
  * @param host
  *            主机
  * @param port
  *            端口
  * @param username
  *            用户名
  * @param password
  *            密码
  * @return
  */
 public ChannelSftp connect(String host, int port, String username,
   String password) {
  ChannelSftp sftp = null;
  try {
   JSch jsch = new JSch();
   jsch.getSession(username, host, port);
   Session sshSession = jsch.getSession(username, host, port);
   System.out.println("Session created.");
   sshSession.setPassword(password);
   Properties sshConfig = new Properties();
   sshConfig.put("StrictHostKeyChecking", "no");
   sshSession.setConfig(sshConfig);
   sshSession.connect();
   System.out.println("Session connected.");
   System.out.println("Opening Channel.");
   Channel channel = sshSession.openChannel("sftp");
   channel.connect();
   sftp = (ChannelSftp) channel;
   // sshSession.disconnect();
   System.out.println("Connected to " + host + ".");
  } catch (Exception e) {

}
  return sftp;
 }

/**
  * 上传文件
  * 
  * @param directory
  *            上传的目录
  * @param uploadFile
  *            要上传的文件
  * @param sftp
  */
 public void upload(String directory, String uploadFile, ChannelSftp sftp) {
  try {
   sftp.cd(directory);
   File file = new File(uploadFile);
   sftp.put(new FileInputStream(file), file.getName());
  } catch (Exception e) {
   e.printStackTrace();
  }
 }

/**
  * 下载文件
  * 
  * @param directory
  *            下载目录
  * @param downloadFile
  *            下载的文件
  * @param saveFile
  *            存在本地的路径
  * @param sftp
  */
 public void download(String directory, String downloadFile,
   String saveFile, ChannelSftp sftp) {
  try {
   sftp.cd(directory);
   File file = new File(saveFile);
   sftp.get(downloadFile, new FileOutputStream(file));
  } catch (Exception e) {
   e.printStackTrace();
  }
 }

/**
  * 删除文件
  * 
  * @param directory
  *            要删除文件所在目录
  * @param deleteFile
  *            要删除的文件
  * @param sftp
  */
 public void delete(String directory, String deleteFile, ChannelSftp sftp) {
  try {
   sftp.cd(directory);
   sftp.rm(deleteFile);
  } catch (Exception e) {
   e.printStackTrace();
  }
 }

/**
  * 列出目录下的文件
  * 
  * @param directory
  *            要列出的目录
  * @param sftp
  * @return
  * @throws SftpException
  */
 public Vector<LsEntry> listFiles(String directory, ChannelSftp sftp)
   throws SftpException {
  return sftp.ls(directory);
 }

public static void main(String[] args) {    
     Jsch4Sftp sf = new Jsch4Sftp();    
        String host = "***";    
        int port = 22; 
        String username = "***";    
        String password = "***";    
        String directory = "/home";    
        String saveFile = "1.zip";    
        String downLoadDirectory = "D:\\";    
        ChannelSftp sftp = null;    
        Session sshSession = null;
        try {    
            JSch jsch = new JSch();    
            jsch.getSession(username, host, port);   
            sshSession = jsch.getSession(username, host, port);
            System.out.println("Session created.");    
            sshSession.setPassword(password);   
            Properties sshConfig = new Properties();    
            sshConfig.put("StrictHostKeyChecking", "no");    
            sshSession.setConfig(sshConfig);   
            sshSession.connect();   
            System.out.println("Session connected.");    
            System.out.println("Opening Channel.");    
            Channel channel = sshSession.openChannel("sftp");    
            channel.connect();   
            sftp = (ChannelSftp) channel;   
            System.out.println("Connected to " + host + ".");    
               
               
               
//          sf.upload(directory, uploadFile, sftp);    
//          sf.download(directory, downloadFile, saveFile, sftp);    
    //      sf.delete(directory, deleteFile, sftp);    
           
//          sftp.cd(directory);    
               
               
            Vector<LsEntry> v = sf.listFiles(directory, sftp);   
            for (LsEntry e : v) {    
                if(!e.getFilename().startsWith(".")) {    
                    saveFile = downLoadDirectory + e.getFilename();   
                    sf.download(directory, e.getFilename(), saveFile, sftp);   
                }   
            }   
            System.out.println("finished");    
        } catch (Exception e) {    
            e.printStackTrace();   
        } finally {    
            sftp.exit();   
            sshSession.disconnect();   
        }   
    }}