Multithreaded client: which listener to use?

I've got a client program that needs to talk to a server. Instead of building in all the RMI and server-aware stuff into the client, I'm making a layer between then, called ClientHookup. This way, we can write alternate front-ends, and just make sure they all talk nicely with ClientHookup.
ClientHookup will receive requests for data from the client (returning a request ID), spawn a thread to process the request, and then notify the client when the data has arrived. This way the client is free to do things while data is coming, it's not just locked up.
I need to make my client implement a listener interface of some sort (like ActionListener), and register this with the ClientHookup, so I can snag events as data is returned.
Am I doing this right? Is there an example somewhere I could look at? What kind of listener should I implement? What kinds of events do I throw?
ActionListener seems to be in java.awt, but I don't really need that stuff. There is an EventListener, but it seems to be a "tagging" interface, whatever that is.
Thanks!
--- Eric

Actually, I found a very wonderful explanation of how to use events and listeners (how to build you own, basically) in another thread. So, never mind! I have what I need.
--- Eric

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Raj Mareddi wrote:
Thanks Levi and Sebastian.
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Edited by: Levi Pereira on Nov 8, 2011 4:23 PM

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see the file listener.ora. path is usually, $ORACLE_HOME/network/admin/listener.ora
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Details will be usually like this
>
LSNR1 =
(DESCRIPTION_LIST =
(DESCRIPTION =
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>
>
if i create listener then a service also created. if i stopped that service and then can i fire query OR Login again, WHAT will be the expected result.
I tried by asking people for my answer. but not satisfied.
>
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check this,
C:\Windows\system32>lsnrctl stop
LSNRCTL for 32-bit Windows: Version 10.2.0.3.0 - Production on 03-MAY-2011 23:06
:22
Copyright (c) 1991, 2006, Oracle. All rights reserved.
Connecting to (DESCRIPTION=(ADDRESS=(PROTOCOL=IPC)(KEY=EXTPROC1)))
The command completed successfully
C:\Windows\system32>sqlplus ganesh
SQL*Plus: Release 10.2.0.3.0 - Production on Tue May 3 23:06:36 2011
Copyright (c) 1982, 2006, Oracle. All Rights Reserved.
Enter password:
Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.3.0 - Production
With the Partitioning, OLAP and Data Mining options
SQL> select * from dual;
D
X
SQL>But if you try to connect from a client, or use the instance name while connectineg
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Enter password: ******
ERROR:
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SQL> If you see, I used the instance name @ganesh.
G.

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Multithreaded client: which listener to use?

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