Java socket - unsure road to take!

Hi all,
We have an application requiring data transfer from a JSP Web application (socket client) and a stand-alone java application (socket server).
This java stand-alone app communicates to an industrial microcontroller connected to the RS-232 serial port.
When this java apps received a command from the JSP web app, it cannot service any other command from other uses, since there is just one RS-232 serial port on the computer. We would like to rely on the java & network environment to buffer additional commands receive simultaneously, as opposed to write code on the java socket server to handle this. In other works, our java stand-alone operates in an assynchronous, single-task mode.
We are unsure which approach to take as far as java socket goes:
1) simple socket server/client;
2) multithread socket
3) pooled
Can anyone advise us.
Thank you
Trajano

Hi Pete,
1) Yes, we can have more than one user trying to access the micro-controllers, because we have in reality a network of micro-controllers connected to the single RS-232 computer port via a RS-485 to RS-232 converter;
2) If a second user tries to issue a command to micro-controller, I would prefer for the java socket/environment to take care of the buffering, by just delaying the response, until the first user gets its command serviced
3) If there is 1 user, him/her might issue several commands at the same time, by opening several JSP pages;
4) No the controllers can service any instruction coming up at any time. The protocol is master/slave. The java app issues a request and the micro-controlle replies back and ready to accept any other request.
ISSUE: My preference is for the system to take care of commands arriving at the socket server.
This java app has two threads:
1) Thread1 is the java socket server and upon receiving a command it will update three (3) properties:
micro-controller address, command and product code
2) Thread32 will be responsible for polling the 3 properties to check if they've changed. Upon detecting a change, it will build the data string and send to the RS-232 serial port.
Any ideas/suggestions.
Thanks in advance for any assistance.
Regards

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