ansaurus

Question

How to create Java socket that is localhost only?

Answer 1

A:

You can't have a "Unix domain socket"-like thing with Java because Java was designed to be cross-platform. However, that's the case without a third party library. I haven't dealt with it myself, but you can take a look at this project and see if it's what you need.

And of course, you'll be able to use it on *nix systems only.

Good luck!

shinkou 2010-02-05 04:43:11

-1 - he doesn't want a "Unix domain socket". He wants a socket on the lookback interface; i.e. on 127.0.0.1.

Stephen C 2010-02-05 05:07:24

Yes, but that's the only way which guarantees the server only accepts local connections. i.e. "localhost" could be mapped to something else, depending on the network settings, although it is not very likely to be the case.

shinkou 2010-02-08 01:43:40

Answer 2

+4 A:

Try

new ServerSocket(9090, 0, InetAddress.getByName("localhost"))

The last parameter to the constructor specifies which address to bind the listening socket to.

Geoff Reedy 2010-02-05 04:45:34

+1 - but bear in mind that some machines don't understand "localhost". So using the IP address 127.0.0.1 is probably more robust.

Stephen C 2010-02-05 05:11:21

Is that really how that constructor works? I had posted that suggestion, but after rereading the description, thought that it sounds like that constructor just chooses only one network connection to accept connections on, instead of all of them (if the system has more than one network device).

Kaleb Brasee 2010-02-05 13:38:29

@Stephen that could cause problems in the future with a host that is primarily IPv6 or even IPv6 only.

Geoff Reedy 2010-02-05 14:22:18

@Kaleb yeah, in principle the localhost address is considered to be a separate network device, usually referred to as the loopback device.

Geoff Reedy 2010-02-05 14:23:48

@Geoff - so either you are screwed because some (real windows) machine does not have a "localhost" entry, or because some (hypothetical) machine is does not support IPv4.

Stephen C 2010-02-05 22:32:19

-1 for believing "localhost" is always mapped to the local machine.

shinkou 2010-02-08 01:49:01

Answer 3

+1 A:

Check this other question and the given answers: How to determine an incoming connection is from local machine

Abel Morelos 2010-02-05 04:53:36

Answer 4

+1 A:

new ServerSocket(9090, 0, InetAddress.getByName("127.0.0.1"));

EJP 2010-02-15 02:57:33

Answer 5

A:

Taken from another question:

new ServerSocket(9090, 0, InetAddress.getByName(null));

InetAddress.getByName(null) points to the loopback address (127.0.0.1)

And here's the Javadoc where it says that

Matías 2010-06-08 04:33:20

ansaurus

tags:

views:

answers:

How to create Java socket that is localhost only?

related questions