TCP tunneling through authenticating HTTP proxy

[Vasiliy Baranov]

Greetings,

And apologies if I am sending this to the wrong list...

Suppose I want my code to talk to a TCP server via an HTTP proxy, by 
setting up a proxy tunnel using the CONNECT method. By any chance, is 
there a mechanism in the Java SE networking stack that would allow me to 
do so? A mechanism that would handle proxy selection, tunneling, and, 
most importantly, authentication identically to HttpURLconnection?

If there is no such mechanism in JDK 7, could such a mechanism be added 
in JDK 8?

FWIW, proxy selection and tunneling through non-authenticating proxy is 
not too difficult to implement with ProxySelector and plain Sockets, 
using sun.net.www.protocol.http.HttpURLConnection.plainConnect as a 
reference. My code does so already.

Proxy authentication, however, is a totally different story. If I parse 
JDK code correctly, client code that does not use HttpURLConnection is 
unlikely to be able to integrate nicely with the AuthCacheValue cache or 
handle complex authentication schemes, unless it chooses to depend on 
some JDK-internal APIs and duplicate great amount of JDK code. My code 
probably cannot afford the latter two, that is why I am asking for help 
here on this list. Since I have proxy selection and non-authenticated 
tunneling already implemented, in my case it would actually be 
sufficient to only have some JDK support for proper integration with the 
AuthCacheValue cache and the standard authentication schemes. However, I 
gather a more universal HTTP tunneling facility, something that works 
like HttpURLConnection but skips the final HTTP handshake with the end 
server, is likely to be a cleaner solution.

If it matters, I am asking this in the context of adding support for 
WebSockets to JavaFX WebView: http://javafx-jira.kenai.com/browse/RT-14947

Thank you in advance,
-- Vasiliy