请给出一个上传文件的例子及代码?谢谢

Question

向FTP服务器上上传一个文件 void putButton_actionPerformed(ActionEvent e) { 
String server=serverEdit.getText(); 
String user=userEdit.getText(); 
String password=passwordEdit.getText(); 
String path=pathEdit.getText(); 
String filename=filenameEdit.getText(); 
try { 
FtpClient ftpClient=new FtpClient(); 
ftpClient.openServer(server); 
ftpClient.login(user, password); 
if (path.length()!=0) ftpClient.cd(path); 
ftpClient.binary(); 
TelnetOutputStream os=ftpClient.put(filename); 
File file_in=new File(filename); 
FileInputStream is=new FileInputStream(file_in); 
byte[] bytes=new byte[1024]; 
int c; 
while ((c=is.read(bytes))!=-1){ 
os.write(bytes,0,c);} 
is.close(); 
os.close(); 
ftpClient.closeServer(); 
} catch (IOException ex) {;} 
} 
}