java实现ftp上传 如何创建文件夹

public boolean connect(String path, String addr, int port, String username, String password) {
    try {
      //FTPClient ftp = new FTPHTTPClient(addr, port, username, password);
      ftp = new FTPClient();
      int reply;
      ftp.connect(addr);
      System.out.println("连接到：" + addr + ":" + port);
      System.out.print(ftp.getReplyString());
      reply = ftp.getReplyCode();
 
      if (!FTPReply.isPositiveCompletion(reply)) {
        ftp.disconnect();
        System.err.println("FTP目标服务器积极拒绝.");
        System.exit(1);
        return false;
      }else{
        ftp.login(username, password);
        ftp.enterLocalPassiveMode();
        ftp.setFileType(FTPClient.BINARY_FILE_TYPE);
        ftp.changeWorkingDirectory(path);
        System.out.println("已连接：" + addr + ":" + port);
        return true;
      }
    } catch (Exception ex) {
      ex.printStackTrace();
      System.out.println(ex.getMessage());
      return false;
    }
  }

public void createDir(String dirname){
  try{
    ftp.makeDirectory(dirname);
    System.out.println("在目标服务器上成功建立了文件夹: " + dirname);
  }catch(Exception ex){
    System.out.println(ex.getMessage());
  }
}

public void disconnect(){
  try {
    ftp.disconnect();
  } catch (IOException e) {
    e.printStackTrace();
  }
}

public static void main(String[] args) {
  FtpUploadTest ftpupload = new FtpUploadTest();
  if(ftpupload.connect("", "172.39.8.x", 20, "administrator", "abc@123")){
    ftpupload.createDir("/UPLOAD");
    ftpupload.disconnect();
  }
}

/**
* 在当前目录下创建文件夹
*
* @param dir
* @return
* @throws Exception
*/
private boolean createDir(String dir) {
try {
ftpClient.ascii();
StringTokenizer s = new StringTokenizer(dir, "/"); // sign
s.countTokens();
String pathName = ftpClient.pwd();
while (s.hasMoreElements()) {
pathName = pathName + "/" + (String) s.nextElement();
try {
ftpClient.sendServer("MKD " + pathName + "\r\n");
} catch (Exception e) {
e = null;
return false;
}
ftpClient.readServerResponse();
}
ftpClient.binary();
return true;
} catch (IOException e1) {
e1.printStackTrace();
return false;
}
}