java实现ftp上传解决思路

java实现ftp上传
谁能帮忙写个java   ftp上传的例子，感激不尽

------解决方案--------------------
package com.skylink.callcenter.ftp;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;

import sun.net.TelnetOutputStream;
import sun.net.TelnetInputStream;
import sun.net.ftp.FtpClient;

public class download {
String localfilename;

String remotefilename;

FtpClient ftpClient;

// server：服务器名字
// user：用户名
// password：密码
// path：服务器上的路径
public void connectServer(String ip, int port,String user
, String password,String path) {

try {
ftpClient = new FtpClient();
ftpClient.openServer(ip,port);
ftpClient.login(user, password);
System.out.println( "login success! ");
if (path.length() != 0) ftpClient.cd(path);
ftpClient.binary();
} catch (IOException ex) {
System.out.println( "not login ");
System.out.println(ex);
}
}

public void closeConnect() {
try {
ftpClient.closeServer();
System.out.println( "disconnect success ");
} catch (IOException ex) {
System.out.println( "not disconnect ");
System.out.println(ex);
}
}

public void upload() {

this.localfilename = "D://test2//test.txt ";
this.remotefilename = "test.txt ";

try {
TelnetOutputStream os = ftpClient.put(this.remotefilename);
java.io.File file_in = new java.io.File(this.localfilename);
FileInputStream is = new FileInputStream(file_in);
byte[] bytes = new byte[1024];
int c;
while ((c = is.read(bytes)) != -1) {
os.write(bytes, 0, c);
}
System.out.println( "upload success ");
is.close();
os.close();
} catch (IOException ex) {
System.out.println( "not upload ");
System.out.println(ex);
}
}

public void download() {

try {
TelnetInputStream is = ftpClient.get(this.remotefilename);
java.io.File file_in = new java.io.File(this.localfilename);
FileOutputStream os = new FileOutputStream(file_in);
byte[] bytes = new byte[1024];
int c;
while ((c = is.read(bytes)) != -1) {
// System.out.println((char)is.read());
// System.out.println(file_in);
os.write(bytes, 0, c);
}

System.out.println( "download success ");
os.close();
is.close();
} catch (IOException ex) {
System.out.println( "not download ");
System.out.println(ex);
}
}

public void download(String remotePath,String remoteFile,String localFile) {

try {
if (remotePath.length() != 0) ftpClient.cd(remotePath);
TelnetInputStream is = ftpClient.get(remoteFile);
java.io.File file_in = new java.io.File(localFile);
FileOutputStream os = new FileOutputStream(file_in);
byte[] bytes = new byte[1024];
int c;
while ((c = is.read(bytes)) != -1) {
// System.out.println((char)is.read());
// System.out.println(file_in);
os.write(bytes, 0, c);
}

System.out.println( "download success ");
os.close();
is.close();
} catch (IOException ex) {
System.out.println( "not download ");
System.out.println(ex);
}
}

public void download(String remoteFile,String localFile) {