RFR: 8223880: Update sun/net/ftp/FtpURL.java and sun/net/ftp/FtpURLConnectionLeak.java to work with IPv6 addresses

[Daniel Fuchs]

Hi Arthue,

On 14/05/2019 23:57, Arthur Eubanks wrote:
> In test/jdk/sun/net/ftp/FtpURL.java, extendedEnabled is always true. 
> Same with portEnabled and pasvEnabled. 

Yes - I left them there as they were preexisting.
The bits that handles EPSV is a copy paste from another
test and that minimized the changes.

> Is the assumption that all 
> current servers support these modes? If so, why is there a bool to say 
> those modes are not enabled?

I have no idea. EPSV and EPRT have been introduced do
support IPv6, and are replacements for PASV and PORT
which only support IPv4. I would guess that servers
should all support these modes by now.

As to your question - my guess is that this test server
got copy & pasted in many tests and some of them might
want to disable some of these modes for testing purposes.

WRT EPSV/PASV the jdk client tries EPSV ALL first, and
if the server replies with `500 'command not understood'`
it will fallback to PASV.

Because this particular server in the test didn't support
EPSV before - it was using PASV for IPv4 addresses.
I made sure this would continue to happen - so that
what's happening on the client side doesn't change
when testing with IPv4.

PASV and PORT will not work on a machine that only has
IPv6.

best regards,

-- daniel