JSch是Java Secure Channel的缩写。JSch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。
本文只介绍如何使用JSch实现的SFTP功能。
SFTP是Secure File Transfer Protocol的缩写，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。SFTP是使用加密传输认证信息和传输的数据，所以，使用SFTP是非常安全的。但是，由于这种传输方式使用了加密/解密技术，所以传输效率比普通的FTP要低得多，如果您对网络安全性要求更高时，可以使用SFTP代替FTP。（来自百度的解释）
要使用JSch，需要下载它的jar包，请从官网下载它：http://www.jcraft.com/jsch/
package com.ebao.jewel.gs.integration.pub.connection.impl;
import java.io.FileNotFoundException;
import java.io.OutputStream;
import java.net.UnknownHostException;
import java.util.Properties;
import java.util.Vector;
import org.apache.commons.httpclient.auth.AuthenticationException;
import com.ebao.jewel.gs.integration.pub.CommonLog.exception.ExceptionUtil;
import com.ebao.jewel.gs.integration.pub.CommonLog.utils.JewelIntLogUtils;
import com.ebao.jewel.gs.integration.pub.commons.InterfaceUtil;
import com.ebao.jewel.gs.integration.pub.connection.IConnection;
import com.ebao.jewel.gs.integration.pub.constants.InterfaceConstants;
import com.jcraft.jsch.ChannelSftp;
import com.jcraft.jsch.JSch;
import com.jcraft.jsch.JSchException;
import com.jcraft.jsch.Session;
public class JewelSftpClient implements IConnection {
private Session sshSession = null;
private ChannelSftp channelSftp = null;
private int connectTimes = 0;
public boolean connect(String host, int port, String username, String pwd)
throws Exception {
if (sshSession == null || !sshSession.isConnected()) {
JSch jsch = new JSch();
try {
sshSession = jsch.getSession(username, host, port);
} catch (JSchException je) {
// throw new Connection
throw je;
}
}
if (!sshSession.isConnected()) {
InterfaceUtil.batchLog("[TEST] sshSession.connect()");
sshSession.setPassword(pwd);
Properties sshConfig = new Properties();
sshConfig.put("StrictHostKeyChecking", "no");
sshSession.setConfig(sshConfig);
try {
sshSession.connect();
} catch (JSchException ex) {
if (ex.getMessage().indexOf("Session.connect") != -1) {
throw new UnknownHostException(ExceptionUtil.getExceptionMsg(ex));
} else {
throw new AuthenticationException(ExceptionUtil.getExceptionMsg(ex));
}
}
}
InterfaceUtil.batchLog("[TEST] sshSession has connected.");
try {
if (channelSftp == null || !channelSftp.isConnected()) {
InterfaceUtil.batchLog("[TEST] channelSftp.connect()");
channelSftp = (ChannelSftp) sshSession.openChannel("sftp");
channelSftp.connect();
}
InterfaceUtil.batchLog("[TEST] channelSftp has been established.");
return true;
} catch (JSchException je) {
if (connectTimes++ < InterfaceConstants.MAX_CONNECT_TIMES) {
String seq = connectTimes == 1 ? "1st" : connectTimes == 2
? "2nd"
: connectTimes == 3 ? "3rd" : connectTimes + "st";
InterfaceUtil.batchLog("[TEST]" + seq
+ " connection failed. Disconnected "
+ (disconnect() == true ? "succeeded" : "failed"));
long sleepTime = InterfaceUtil.getConnectSleepTime() * 1000L;
Thread.sleep(sleepTime);
InterfaceUtil.batchLog("[TEST]" + sleepTime + " ms passed. Try "
+ (int) (connectTimes + 1) + " connection.");
if (connectTimes == 4) {
InterfaceUtil
.batchLog("[TEST] !!!!!!!!!!!connection goes wrong!!!!!!!!!!!!!!!!");
}
return connect(host, port, username, pwd);
} else {
InterfaceUtil.batchLog("[TEST] connect excceeded 10 times.");
throw je;
}
}
}
public boolean disconnect() throws Exception {
try {
if (channelSftp != null && channelSftp.isConnected()) {
channelSftp.disconnect();
InterfaceUtil.batchLog("[TEST] channelSftp has cloesd.");
}
if (sshSession != null && sshSession.isConnected()) {
sshSession.disconnect();
InterfaceUtil.batchLog("[TEST] sshSession has cloesd.");
}
return true;
} catch (Exception e) {
return false;
}
}
public void upload(String src, String dst) throws Exception {
channelSftp.put(src, dst);
}
public void download(String src, String dst) throws Exception {
channelSftp.get(src, dst);
}
@SuppressWarnings("unchecked")
public Vector<Object> listFiles(String directory) throws Exception {
try {
channelSftp.cd(directory);
} catch (Exception e) {
throw new FileNotFoundException("No such file or directory.src:"
+ directory);
}
Vector<Object> files = channelSftp.lsnames(directory);
return files;
}
public boolean moveFile(String src, String dst) throws Exception {
try {
channelSftp.rename(src, dst);
return true;
} catch (Exception e) {
JewelIntLogUtils.batchLog("[TEST] Move the file from " + src + " to "
+ dst + " fail", e);
throw e;
}
}
public boolean isConnected() {
return channelSftp != null && channelSftp.isConnected();
}
@Override
public void download(String src, OutputStream out) throws Exception {
channelSftp.get(src, out);
}
}
代码copy 同事的
转载地址是 ：http://www.cnblogs.com/longyg/archive/2012/06/25/2556576.html