Setting FTP active/passive mode with Java URLConnection

Question

Is it possible to set FTP passive or active mode when working with URLConnection class? I cannot find any documentation on this, yet this is such a basic functionality that

Answer 1

Today, we capture TCP/IP packet and confirm that the Android/JAVA/URLConnection still use PORT(Active mode) for FTP.

If the server don't support active mode or the network don't support active mode, the URLConnection will failed.

Answer 2

To get FTP full fledged to work, you'll really need to fall back to low-level programming with Sockets. The URLConnection and consorts simply doesn't suit your needs (no support to enter into passive mode). Fortunately Apache Commons has already done a lot of work for you in flavor of Apache Commons Net FTPClient. To achieve what you need, just use FTPClient#enterLocalPassiveMode() or FTPClient#enterLocalActiveMode()