近来应需求需要，做了服务器之间的文件传输，利用的ssh协议。查阅各种资料博客，基本都是下载文件的方法，找不到下载文件夹得方法。思索多日写了一个下载文件夹的简单方法，可能步骤繁琐，优化不大好。由于jsch不能得到服务器端文件的绝对路径，目前还没能想出怎么遍历下载文件夹和文件。只好利用ssh2 jar包的session方法操作Linux命令实现下载。话不多说，直接上代码。

一：导入的jar包，jar包在Apache可以自己下载

import java.io.BufferedInputStream;

import java.io.BufferedReader;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.io.OutputStream;

import java.io.UnsupportedEncodingException;

import java.util.ResourceBundle;

import java.util.zip.GZIPInputStream;

import org.apache.tools.tar.TarEntry;

import org.apache.tools.tar.TarInputStream;

import ch.ethz.ssh2.Connection;

import ch.ethz.ssh2.SCPClient;

import ch.ethz.ssh2.Session;

import ch.ethz.ssh2.StreamGobbler;

二：类和方法

/**

*

* @param dataServerIp 服务器IP

* @param dataServerUsername 服务器用户名

* @param dataServerPassword 服务器登录密码

* @param srcFile 要下载的文件路径

* @param saveFile 保存路径

* @param port 端口号，null时为默认端口

*/

public static void downLoadFile(String dataServerIp,String dataServerUsername,String dataServerPassword,String srcFile,String saveFile,int port){

Connection conn = new Connection(dataServerIp);

Session session = null;

SCPClient client =null;

//session=(Session) getObject(dataServerIp, dataServerUsername, dataServerPassword, 0, "session");

//client=(SCPClient) getObject(dataServerIp, dataServerUsername, dataServerPassword, 0, "client");

conn=getConn(dataServerIp, dataServerUsername, dataServerPassword, 22);

try {

session=conn.openSession();

client=conn.createSCPClient();

} catch (IOException e1) {

e1.printStackTrace();

}

try {

boolean flag=download(srcFile, saveFile, session, client);

//如果是打包文件，删除包裹

if (flag) {

System.out.println("文件打包下载完成！");

//解压tar.gz包

String fileName=srcFile.substring(srcFile.lastIndexOf("/")+1);

File file=new File(saveFile+"/"+fileName+".tar.gz");

unTarGz(file, saveFile);

System.out.println("文件解压完成！");

//解压完后删除本地压缩包

file.delete();

String cmdDel="rm -rf "+srcFile+".tar.gz";

session=(Session) getObject(dataServerIp, dataServerUsername, dataServerPassword, 0, "session");

//删除服务器生成的压缩包

session.execCommand(cmdDel);

}else {

System.out.println("文件下载完成！");

}

} catch (UnsupportedEncodingException e) {

e.printStackTrace();

} catch (IOException e) {

// TODO Auto-generated catch block

e.printStackTrace();

}finally {

session.close();

conn.close();

}

}

/**

* 根据不同的需求得到相应的连接

* @param ip

* @param userName

* @param pwd

* @param port

* @param whatWant 必须是client或者session

* @return

*/

public static Object getObject(String ip,String userName,String pwd,int port,String whatWant){

Connection conn = new Connection(ip);

Session session = null;

SCPClient client =null;

try {

conn.connect();

boolean isAuthenticated = conn.authenticateWithPassword(userName, pwd);

session=conn.openSession();

client = new SCPClient(conn);

if (isAuthenticated == false) {

throw new IOException("Authentication failed.文件scp到数据服务器时发生异常");

}

} catch (IOException e) {

e.printStackTrace();

}

if (whatWant!=null&&whatWant.equals("session")) {

return session;

}if (whatWant!=null&&whatWant.equals("client")) {

return client;

}

return null;

}

/**

* 获得连接

* @param ip

* @param userName

* @param pwd

* @param port

* @return

*/

public static Connection getConn(String ip,String userName,String pwd,int port){

Connection conn = new Connection(ip);

boolean blag=false;

try {

conn.connect();

boolean isAuthenticated = conn.authenticateWithPassword(userName, pwd);

//session=conn.openSession();

// client = new SCPClient(conn);

if (isAuthenticated) {

blag=true;

}

if (isAuthenticated == false) {

throw new IOException("Authentication failed.文件scp到数据服务器时发生异常");

}

} catch (IOException e) {

e.printStackTrace();

}

if (blag) {

return conn;

}else {

return null;

}

}

/**

*

* @param srcFile 要下载的文件

* @param saveFile 保存目录，必须是目录

* @param sessionSsh

* @param client

* @return

* @throws UnsupportedEncodingException

*/

public static boolean download(String srcFile, String saveFile, Session sessionSsh, SCPClient client

) throws UnsupportedEncodingException {

//String cdmTar="tar czf /var/ftp/upload/ruku/ruku.tar.gz –directory=/var/ftp/upload/ruku ruku";

boolean flag=false;

// 是文件,直接下载

try {

String filename=srcFile.substring(srcFile.lastIndexOf("/")+1);

if (filename.contains(".")) {

try {

client.get(srcFile, saveFile);

} catch (Exception e) {

//是文件夹，打包下载

String src=srcFile.substring(0, srcFile.lastIndexOf("/"));

String cmdGet = "tar -zcvf " + srcFile + ".tar.gz " + filename;

//String cmdGet="tar czf /home/"+filename+".tar.gz –directory="+src+"/"+filename+".";

// 执行压缩命令

sessionSsh.execCommand("cd "+src+";"+cmdGet);

InputStream stdout = new StreamGobbler(sessionSsh.getStdout());

BufferedReader br = new BufferedReader(new InputStreamReader(stdout));

// cmriots!@#

while (true) {

String line = br.readLine();

if (line == null)

break;

System.out.println(line);

}

System.out.println("ExitCode: " + sessionSsh.getExitStatus());

// 下载文件

client.get(src+"/"+filename+".tar.gz", saveFile);

flag=true;

e.printStackTrace();

}

}else {

//是文件夹，打包下载

String src=srcFile.substring(0, srcFile.lastIndexOf("/"));

String cmdGet = "tar -zcvf " + srcFile + ".tar.gz " + filename;

//String cmdGet="tar czf /home/"+filename+".tar.gz –directory="+src+"/"+filename+".";

// 执行压缩命令

sessionSsh.execCommand("cd "+src+";"+cmdGet);

InputStream stdout = new StreamGobbler(sessionSsh.getStdout());

BufferedReader br = new BufferedReader(new InputStreamReader(stdout));

// cmriots!@#

while (true) {

String line = br.readLine();

if (line == null)

break;

System.out.println(line);

}

System.out.println("ExitCode: " + sessionSsh.getExitStatus());

// 下载文件

client.get(src+"/"+filename+".tar.gz", saveFile);

//unGzipFile(saveFile+"/"+filename+".tar.gz");

flag=true;

}

} catch (IOException e) {

e.printStackTrace();

}

return flag;

}

//------------------------------------------------------------------------------------------------------

/**

* 解压tar.gz 文件

* @param file 要解压的tar.gz文件对象

* @param outputDir 要解压到某个指定的目录下

* @throws IOException

*/

public static void unTarGz(File file,String outputDir) throws IOException{

TarInputStream tarIn = null;

try{

tarIn = new TarInputStream(new GZIPInputStream(

new BufferedInputStream(new FileInputStream(file))),

1024 * 2);

createDirectory(outputDir,null);//创建输出目录

TarEntry entry = null;

while( (entry = tarIn.getNextEntry()) != null ){

if(entry.isDirectory()){//是目录

entry.getName();

createDirectory(outputDir,entry.getName());//创建空目录

}else{//是文件

File tmpFile = new File(outputDir + "/" + entry.getName());

createDirectory(tmpFile.getParent() + "/",null);//创建输出目录

OutputStream out = null;

try{

out = new FileOutputStream(tmpFile);

int length = 0;

byte[] b = new byte[2048];

while((length = tarIn.read(b)) != -1){

out.write(b, 0, length);

}

}catch(IOException ex){

throw ex;

}finally{

if(out!=null)

out.close();

}

}

}

}catch(IOException ex){

throw new IOException("解压归档文件出现异常",ex);

} finally{

try{

if(tarIn != null){

tarIn.close();

}

}catch(IOException ex){

throw new IOException("关闭tarFile出现异常",ex);

}

}

}

/**

* 构建目录

* @param outputDir

* @param subDir

*/

public static void createDirectory(String outputDir,String subDir){

File file = new File(outputDir);

if(!(subDir == null || subDir.trim().equals(""))){//子目录不为空

file = new File(outputDir + "/" + subDir);

}

if(!file.exists()){

if(!file.getParentFile().exists())

file.getParentFile().mkdirs();

file.mkdirs();

}

}楼主亲测可用，建类复制方法即可。