如何使用Java从FTPS服务器获取文件？

Question

I'm trying to acess a folder in a path i created in a ftps server but it returns nothing, it's connecting but does not return anything, if i change the server configuration to just ftp it works. I'm using FileZilla Server and the its configurations is above.

SSL/TLS

Flag true Enable FTP over SSL/TLS support (FTPS) and Allow explicit FTP over TLS at SSL/TLS settings

My user configuration is:

Flat "Force SSL for user login" is true at General of user configuration at FireZilla Server.

The server's log about the connection is getting a message, i dont know if it helps:

227 Entering Passive Mode

LIST

521 PROT P required

PASV

227 Entering Passive Mode

NLST

521 PROT P required

Quit

My example class to connect is above with every permissions:

public class FTPClientExample2 {

public static void main(String[] args)
{
    String server = "myip";
    int port = 2121;
    String user = "joao";
    String pass = "1234";

    boolean error = false;
    FTPSClient ftp = null;
    try
    {
        ftp = new FTPSClient("SSL");
        ftp.setAuthValue("SSL");
        ftp.addProtocolCommandListener(new PrintCommandListener(new PrintWriter(System.out)));

        int reply;

        ftp.connect(server, port);
        System.out.println("Connected to ftp.wpmikz.com.cn");
        System.out.print(ftp.getReplyString());

        // After connection attempt, you should check the reply code to verify
        // success.
        reply = ftp.getReplyCode();

        if (!FTPReply.isPositiveCompletion(reply))
        {
            ftp.disconnect();
            System.err.println("FTP server refused connection.");
            System.exit(1);
        }
        ftp.login(user, pass);
        // ... // transfer files
        ftp.setBufferSize(1000);
        ftp.enterLocalPassiveMode();
        // ftp.setControlEncoding("GB2312");
        ftp.changeWorkingDirectory("/");
        ftp.changeWorkingDirectory("/ae"); //path where my files are
        ftp.setFileType(FTP.BINARY_FILE_TYPE);
        System.out.println("Remote system is " + ftp.getSystemName());

        String[] tmp = ftp.listNames();  //returns null
        System.out.println(tmp.length);
    }
    catch (IOException ex)
    {
        System.out.println("Oops! Something wrong happened");
        ex.printStackTrace();
    }
    finally
    {
        // logs out and disconnects from server
        try
        {
            if (ftp.isConnected())
            {
                ftp.logout();
                ftp.disconnect();
            }
        }
        catch (IOException ex)
        {
            ex.printStackTrace();
        }
    }
}

}

Any idea what is wrong?

Thank you all!

Answer 1

Try to execute this after the login

  ftp.execPBSZ(0);
  ftp.execPROT("P");