I am trying to use the FTPSClient class from Apache Commons Net 3.9.0 just to list files on the server. Here is my code:
public static void main(String[] args) throws IOException {
FTPSClient ftpClient = new FTPSClient();
ftpClient.connect("127.0.0.1");
ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
ftpClient.enterLocalPassiveMode();
ftpClient.login("user", "");
ftpClient.execPBSZ(0L);
ftpClient.execPROT("P");
for (FTPFile ftpFile : ftpClient.listFiles()) {
System.out.println(ftpFile.getName());
}
ftpClient.disconnect();
}
The significant logs from the server are:
FTP Session 18 127.0.0.1 user [Command] LIST
FTP Session 18 127.0.0.1 user [Response] 150 Starting data transfer.
FTP Session 18 127.0.0.1 user [Error] TLS session of data connection not resumed.
FTP Session 18 127.0.0.1 user [Response] 425 Unable to build data connection: TLS session of data connection not resumed.
FTP Session 18 127.0.0.1 user [Error] Received TLS alert from the client: User canceled (90)
What is the problem here? In addition, the server works using explicit FTPS.