Handle multiple connections on server side

Hi,
I am trying to enable many clients to connect to my server at the same time.
So far what i have done is to create a serverSocket named theSocket
and accept incomming connection : theSocket.accept().
Each time a connection is established my server create a new Thread to deal with that client: which means one client = one thread running on the Server. But if i have Many clients like 1000...
that would mean 1000 Threads running on the server and i think this is weak in terms of performance in server side.
Any idea about how to improve this?
thanks
seb

I think you need to ues Java NIO

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URGENT:Handle multiple connection in a multithreaded server.

I hava a multithreaded server where it can handle multiple connection.
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2) How can I stop the server, clean up the thread and start the server again for waiting new connection? Currently, I can just start my server once.
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server = new ServerSocket(5000);
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server1frame sframe=null;
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1) Let say that my server can handle multiple
connections. This is to cater for the different
requests from the client. For instance, the client may
make one connection for chatting and another
connection for sending file(something like we have in
Yahoo Messanger). So, at the server side, how can I
differentiate between the connection for CHAT and the
connection for SEND FILE so that I can handle the
requests separately. It means I can save the file sent
from client and display the chat message in the
JTextArea?Either your server listens on two different ports for two different protocolls, (then you would a server thread for each port) or you accept connections for both protocolls on both ports, and have the client state what protocoll it is using :
eg:
accept Connection - start new Thread - read first line - depending on protocoll pass protocoll object (CHAT, FTP) to run method
There is an example for a simple protocoll at : http://java.sun.com/docs/books/tutorial/networking/sockets/clientServer.html
2) How can I stop the server, clean up the thread and
start the server again for waiting new connection?
Currently, I can just start my server once.You normally start servers only once. It should then be up and listening for it's entire lifetime. Restarting a server should only be needed if it hangs or crashes.

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http://www.javaworld.com/javaworld/javatips/jw-javatip136.html
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          // xar3.start(RESUME);
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          connHandle.doSomeWork();
          connHandle.close()
          // xar3.end(SUSPEND);
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          // xar3.end(SUCCESS);
          // xar3.commit(onephase = true);
          // managedConn3.cleanup();
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          What's more puzzling, it's that when monitoring my connector with the
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Handle multiple connections on server side

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