Question

I am trying to figure out how to create a java program that can listen to multiple ports and perform different actions depending on which port the client speaks to.

I’ve seen and understand the basic client-server program:
http://systembash.com/content/a-simple-java-tcp-server-and-tcp-client/

Just to reiterate, I want to create this same relationship, but instead of the server only listening on one port and performing one action when it receives input, I want it to listen on multiple ports and depending which port the client connects and sends data to, perform a different action.

I’m hoping to make each port accept a GET and PUT command in the future, but for now I’m just trying to figure out how to set up the basic structure of the server which will be able to listen to multiple ports. I’ve tried googling, but I can’t seem to find much, so any help is appreciated.

Thanks in advance.
-Anthony

Answer 1

A socket can only be open to a particular port, so you need multiple server sockets (e.g. 1 socket per port). I think you also need one thread per socket so that network activity on one socket doesn’t interfere with activity on the others.

Are you implementing a server as an academic exercise? If not, I’d really really really really strongly recommend using a preexisting server, like Tomcat.