JAVA SFTP文件上传、下载及批量下载

1.jsch官方API查看地址（附件为需要的jar）
http://www.jcraft.com/jsch/ 

2.jsch简介
JSch(Java Secure Channel)是一个SSH2的纯Java实现。它允许你连接到一个SSH服务器，并且可以使用端口转发，X11转发，文件传输等，当然你也可以集成它的功能到你自己的应用程序。
  SFTP(Secure File Transfer Protocol)安全文件传送协议。可以为传输文件提供一种安全的加密方法。SFTP 为 SSH的一部份，是一种传输文件到服务器的安全方式，但是传输效率比普通的FTP要低。 

3.api常用的方法：
put()：      文件上传
get()：      文件下载
cd()：       进入指定目录
ls()：       得到指定目录下的文件列表
rename()：   重命名指定文件或目录
rm()：       删除指定文件
mkdir()：    创建目录
rmdir()：    删除目录
put和get都有多个重载方法，自己看源代码 

4.对常用方法的使用,封装成一个util类
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Properties;
import java.util.Vector;

import org.apache.log4j.Logger;

import com.jcraft.jsch.Channel;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.Session;
import com.jcraft.jsch.SftpATTRS;
import com.jcraft.jsch.SftpException;
import com.jcraft.jsch.ChannelSftp.LsEntry;
/**
 * sftp工具类
 *
 * @author xxx
 * @date 2014-6-17
 * @time 下午1:39:44
 * @version 1.0
 */
public class SFTPUtils
{
    private static Logger log = Logger.getLogger(SFTPUtils.class.getName());

    private String host;//服务器连接ip
    private String username;//用户名
    private String password;//密码
    private int port = 22;//端口号
    private ChannelSftp sftp = null;
    private Session sshSession = null;

    public SFTPUtils(){}

    public SFTPUtils(String host, int port, String username, String password)
    {
        this.host = host;
        this.username = username;
        this.password = password;
        this.port = port;
    }

    public SFTPUtils(String host, String username, String password)
    {
        this.host = host;
        this.username = username;
        this.password = password;
    }

    /**
     * 通过SFTP连接服务器
     */
    public void connect()
    {
        try
        {
            JSch jsch = new JSch();
            jsch.getSession(username, host, port);
            sshSession = jsch.getSession(username, host, port);
            if (log.isInfoEnabled())
            {
                log.info("Session created.");
            }
            sshSession.setPassword(password);
            Properties sshConfig = new Properties();
            sshConfig.put("StrictHostKeyChecking", "no");
            sshSession.setConfig(sshConfig);
            sshSession.connect();
            if (log.isInfoEnabled())
            {
                log.info("Session connected.");
            }
            Channel channel = sshSession.openChannel("sftp");
            channel.connect();
            if (log.isInfoEnabled())
            {
                log.info("Opening Channel.");
            }
            sftp = (ChannelSftp) channel;
            if (log.isInfoEnabled())
            {
                log.info("Connected to " + host + ".");
            }
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 关闭连接
     */
    public void disconnect()
    {
        if (this.sftp != null)
        {
            if (this.sftp.isConnected())
            {
                this.sftp.disconnect();
                if (log.isInfoEnabled())
                {
                    log.info("sftp is closed already");
                }
            }
        }
        if (this.sshSession != null)
        {
            if (this.sshSession.isConnected())
            {
                this.sshSession.disconnect();
                if (log.isInfoEnabled())
                {
                    log.info("sshSession is closed already");
                }
            }
        }
    }

    /**
     * 批量下载文件
     * @param remotPath：远程下载目录(以路径符号结束,可以为相对路径eg:/assess/sftp/jiesuan_2/2014/)
     * @param localPath：本地保存目录(以路径符号结束,D:\Duansha\sftp\)
     * @param fileFormat：下载文件格式(以特定字符开头,为空不做检验)
     * @param fileEndFormat：下载文件格式(文件格式)
     * @param del：下载后是否删除sftp文件
     * @return
     */
    public List<String> batchDownLoadFile(String remotePath, String localPath,
            String fileFormat, String fileEndFormat, boolean del)
    {
        List<String> filenames = new ArrayList<String>();
        try
        {
            // connect();
            Vector v = listFiles(remotePath);
            // sftp.cd(remotePath);
            if (v.size() > 0)
            {
                System.out.println("本次处理文件个数不为零,开始下载...fileSize=" + v.size());
                Iterator it = v.iterator();
                while (it.hasNext())
                {
                    LsEntry entry = (LsEntry) it.next();
                    String filename = entry.getFilename();
                    SftpATTRS attrs = entry.getAttrs();
                    if (!attrs.isDir())
                    {
                        boolean flag = false;
                        String localFileName = localPath + filename;
                        fileFormat = fileFormat == null ? "" : fileFormat
                                .trim();
                        fileEndFormat = fileEndFormat == null ? ""
                                : fileEndFormat.trim();
                        // 三种情况
                        if (fileFormat.length() > 0 && fileEndFormat.length() > 0)
                        {
                            if (filename.startsWith(fileFormat) && filename.endsWith(fileEndFormat))
                            {
                                flag = downloadFile(remotePath, filename,localPath, filename);
                                if (flag)
                                {
                                    filenames.add(localFileName);
                                    if (flag && del)
                                    {
                                        deleteSFTP(remotePath, filename);
                                    }
                                }
                            }
                        }
                        else if (fileFormat.length() > 0 && "".equals(fileEndFormat))
                        {
                            if (filename.startsWith(fileFormat))
                            {
                                flag = downloadFile(remotePath, filename, localPath, filename);
                                if (flag)
                                {
                                    filenames.add(localFileName);
                                    if (flag && del)
                                    {
                                        deleteSFTP(remotePath, filename);
                                    }
                                }
                            }
                        }
                        else if (fileEndFormat.length() > 0 && "".equals(fileFormat))
                        {
                            if (filename.endsWith(fileEndFormat))
                            {
                                flag = downloadFile(remotePath, filename,localPath, filename);
                                if (flag)
                                {
                                    filenames.add(localFileName);
                                    if (flag && del)
                                    {
                                        deleteSFTP(remotePath, filename);
                                    }
                                }
                            }
                        }
                        else
                        {
                            flag = downloadFile(remotePath, filename,localPath, filename);
                            if (flag)
                            {
                                filenames.add(localFileName);
                                if (flag && del)
                                {
                                    deleteSFTP(remotePath, filename);
                                }
                            }
                        }
                    }
                }
            }
            if (log.isInfoEnabled())
            {
                log.info("download file is success:remotePath=" + remotePath
                        + "and localPath=" + localPath + ",file size is"
                        + v.size());
            }
        }
        catch (SftpException e)
        {
            e.printStackTrace();
        }
        finally
        {
            // this.disconnect();
        }
        return filenames;
    }

    /**
     * 下载单个文件
     * @param remotPath：远程下载目录(以路径符号结束)
     * @param remoteFileName：下载文件名
     * @param localPath：本地保存目录(以路径符号结束)
     * @param localFileName：保存文件名
     * @return
     */
    public boolean downloadFile(String remotePath, String remoteFileName,String localPath, String localFileName)
    {
        FileOutputStream fieloutput = null;
        try
        {
            // sftp.cd(remotePath);
            File file = new File(localPath + localFileName);
            // mkdirs(localPath + localFileName);
            fieloutput = new FileOutputStream(file);
            sftp.get(remotePath + remoteFileName, fieloutput);
            if (log.isInfoEnabled())
            {
                log.info("===DownloadFile:" + remoteFileName + " success from sftp.");
            }
            return true;
        }
        catch (FileNotFoundException e)
        {
            e.printStackTrace();
        }
        catch (SftpException e)
        {
            e.printStackTrace();
        }
        finally
        {
            if (null != fieloutput)
            {
                try
                {
                    fieloutput.close();
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
        }
        return false;
    }

    /**
     * 上传单个文件
     * @param remotePath：远程保存目录
     * @param remoteFileName：保存文件名
     * @param localPath：本地上传目录(以路径符号结束)
     * @param localFileName：上传的文件名
     * @return
     */
    public boolean uploadFile(String remotePath, String remoteFileName,String localPath, String localFileName)
    {
        FileInputStream in = null;
        try
        {
            createDir(remotePath);
            File file = new File(localPath + localFileName);
            in = new FileInputStream(file);
            sftp.put(in, remoteFileName);
            return true;
        }
        catch (FileNotFoundException e)
        {
            e.printStackTrace();
        }
        catch (SftpException e)
        {
            e.printStackTrace();
        }
        finally
        {
            if (in != null)
            {
                try
                {
                    in.close();
                }
                catch (IOException e)
                {
                    e.printStackTrace();
                }
            }
        }
        return false;
    }

    /**
     * 批量上传文件
     * @param remotePath：远程保存目录
     * @param localPath：本地上传目录(以路径符号结束)
     * @param del：上传后是否删除本地文件
     * @return
     */
    public boolean bacthUploadFile(String remotePath, String localPath,
            boolean del)
    {
        try
        {
            connect();
            File file = new File(localPath);
            File[] files = file.listFiles();
            for (int i = 0; i < files.length; i++)
            {
                if (files[i].isFile()
                        && files[i].getName().indexOf("bak") == -1)
                {
                    if (this.uploadFile(remotePath, files[i].getName(),
                            localPath, files[i].getName())
                            && del)
                    {
                        deleteFile(localPath + files[i].getName());
                    }
                }
            }
            if (log.isInfoEnabled())
            {
                log.info("upload file is success:remotePath=" + remotePath
                        + "and localPath=" + localPath + ",file size is "
                        + files.length);
            }
            return true;
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        finally
        {
            this.disconnect();
        }
        return false;

    }

    /**
     * 删除本地文件
     * @param filePath
     * @return
     */
    public boolean deleteFile(String filePath)
    {
        File file = new File(filePath);
        if (!file.exists())
        {
            return false;
        }

        if (!file.isFile())
        {
            return false;
        }
        boolean rs = file.delete();
        if (rs && log.isInfoEnabled())
        {
            log.info("delete file success from local.");
        }
        return rs;
    }

    /**
     * 创建目录
     * @param createpath
     * @return
     */
    public boolean createDir(String createpath)
    {
        try
        {
            if (isDirExist(createpath))
            {
                this.sftp.cd(createpath);
                return true;
            }
            String pathArry[] = createpath.split("/");
            StringBuffer filePath = new StringBuffer("/");
            for (String path : pathArry)
            {
                if (path.equals(""))
                {
                    continue;
                }
                filePath.append(path + "/");
                if (isDirExist(filePath.toString()))
                {
                    sftp.cd(filePath.toString());
                }
                else
                {
                    // 建立目录
                    sftp.mkdir(filePath.toString());
                    // 进入并设置为当前目录
                    sftp.cd(filePath.toString());
                }

            }
            this.sftp.cd(createpath);
            return true;
        }
        catch (SftpException e)
        {
            e.printStackTrace();
        }
        return false;
    }

    /**
     * 判断目录是否存在
     * @param directory
     * @return
     */
    public boolean isDirExist(String directory)
    {
        boolean isDirExistFlag = false;
        try
        {
            SftpATTRS sftpATTRS = sftp.lstat(directory);
            isDirExistFlag = true;
            return sftpATTRS.isDir();
        }
        catch (Exception e)
        {
            if (e.getMessage().toLowerCase().equals("no such file"))
            {
                isDirExistFlag = false;
            }
        }
        return isDirExistFlag;
    }

    /**
     * 删除stfp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 deleteSFTP(String directory, String deleteFile)
    {
        try
        {
            // sftp.cd(directory);
            sftp.rm(directory + deleteFile);
            if (log.isInfoEnabled())
            {
                log.info("delete file success from sftp.");
            }
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * 如果目录不存在就创建目录
     * @param path
     */
    public void mkdirs(String path)
    {
        File f = new File(path);

        String fs = f.getParent();

        f = new File(fs);

        if (!f.exists())
        {
            f.mkdirs();
        }
    }

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

    public String getHost()
    {
        return host;
    }

    public void setHost(String host)
    {
        this.host = host;
    }

    public String getUsername()
    {
        return username;
    }

    public void setUsername(String username)
    {
        this.username = username;
    }

    public String getPassword()
    {
        return password;
    }

    public void setPassword(String password)
    {
        this.password = password;
    }

    public int getPort()
    {
        return port;
    }

    public void setPort(int port)
    {
        this.port = port;
    }

    public ChannelSftp getSftp()
    {
        return sftp;
    }

    public void setSftp(ChannelSftp sftp)
    {
        this.sftp = sftp;
    }

    /**测试*/
    public static void main(String[] args)
    {
        SFTPUtils sftp = null;
        // 本地存放地址
        String localPath = "D:/tomcat5/webapps/ASSESS/DocumentsDir/DocumentTempDir/txtData/";
        // Sftp下载路径
        String sftpPath = "/home/assess/sftp/jiesuan_2/2014/";
        List<String> filePathList = new ArrayList<String>();
        try
        {
            sftp = new SFTPUtils("10.163.201.115", "tdcp", "tdcp");
            sftp.connect();
            // 下载
            sftp.batchDownLoadFile(sftpPath, localPath, "ASSESS", ".txt", true);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        finally
        {
            sftp.disconnect();
        }
    }
}

5.需要的时间辅助类，顺带记下，下次可以直接拿来用
/**
 * 时间处理工具类（简单的）
 * @author Aaron
 * @date 2014-6-17
 * @time 下午1:39:44
 * @version 1.0
 */
public class DateUtil {
     /**
     * 默认时间字符串的格式
     */
    public static final String DEFAULT_FORMAT_STR = "yyyyMMddHHmmss";

    public static final String DATE_FORMAT_STR = "yyyyMMdd";

    /**
     * 获取系统时间的昨天
     * @return
     */
    public static String getSysTime(){
         Calendar ca = Calendar.getInstance();
         ca.set(Calendar.DATE, ca.get(Calendar.DATE)-1);
         Date d = ca.getTime();
         SimpleDateFormat sdf =  new SimpleDateFormat("yyyyMMdd");
         String a = sdf.format(d);
        return a;
    }

    /**
     * 获取当前时间
     * @param date
     * @return
     */
    public static String getCurrentDate(String formatStr)
    {
        if (null == formatStr)
        {
            formatStr=DEFAULT_FORMAT_STR;
        }
        return date2String(new Date(), formatStr);
    }

    /**
     * 返回年月日
     * @return yyyyMMdd
     */
    public static String getTodayChar8(String dateFormat){
        return DateFormatUtils.format(new Date(), dateFormat);
    }

    /**
     * 将Date日期转换为String
     * @param date
     * @param formatStr
     * @return
     */
    public static String date2String(Date date, String formatStr)
    {
        if (null == date || null == formatStr)
        {
            return "";
        }
        SimpleDateFormat df = new SimpleDateFormat(formatStr);

        return df.format(date);
    }
}