public static void send (String fileName) throws JSchException, SftpException, FileNotFoundException {
        String PHOST = "***";
        int PORT = 22922;
        String PUSER = "user";
        String PPASS = "pass";
        String PWORKINGDIR = "/a/a/a/a"; // папка на сервере, в которую нужно положить файлы

        Session session = null;
        Channel channel = null;
        ChannelSftp channelSftp = null;
        System.out.println("preparing the host information for sftp.");
       
            JSch jsch = new JSch();
            session = jsch.getSession(PUSER, PHOST, PORT);
            session.setPassword(PPASS);
            java.util.Properties config = new java.util.Properties();
            config.put("StrictHostKeyChecking", "no");
            session.setConfig(config);
            session.connect();
            System.out.println("Host connected.");
            channel = session.openChannel("sftp");
            channel.connect();
            System.out.println("sftp channel opened and connected.");
            channelSftp = (ChannelSftp) channel;
            System.out.println("111");
            channelSftp.cd(PWORKINGDIR); 
            System.out.println("222");
            File f = new File(fileName);
            System.out.println("3333");
            channelSftp.put(new FileInputStream(f), f.getName());
     
    }   

public class TestSFTP {
    public static void main(String[] args){
        NewClass.send("C:/test.txt");
    }
}