Release resource

Hi
I think it is a good practice to release resource (eg, db connection) whenever the user session is ended or time-out.
I do the following things:
class myHttpSerlvet extends HttpServlet implements HttpSessionBindingListener
then all the servlets in my application extend from myHttpServlet.
Then i can release resource in the valueUnbound operation of the servlets.
Am I right? Is there any performance consideration?
Thank you
Leo

Well, this really isn't necessary. The various JDBC classes all implement finalize() to release their resources. So, when the session is destroyed, those objects will be garbage collected and the resources will automatically be removed.
A better plan would be to not have the database connections in the session at all. Instead, use DB connection pooling. For example, javax.sql.PooledConnection. Then you can just keep reusing the same connections and don't have to deal with constantly connecting and disconnecting, and you have better load management on your database.

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Hi THurst,
I will like to step into the forum and suggest a more simple approach, if you can run this shipped example: “Cont Gen Voltage Wfm-Int Clk-Non Regeneration.vi”, and simply write a waveform with amplitude zero, before ending the task. This might be a good resource to look at: What is the Difference Between the DAQmx Stop Task.vi and DAQmx Clear Task.vi? , The screenshot might give you an idea, but basically you press the Boolean to change the amplitude of the sine wave to zero and then you stop the task.
I hope it helps
Message Edited by Jaime F on 12-12-2007 02:48 PM
Jaime Hoffiz
National Instruments
Product Expert
Digital Multimeters and LCR Meters
Attachments:
zero offset.png ‏22 KB

Release Resource from Project during closeout?

Hi,
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Case : 1. Created Requirement
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3. Submit for Approval
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Working with the Development Infrastructure
http://help.sap.com/saphelp_nw04s/helpdata/en/03/f6bc3d42f46c33e10000000a11405a/frameset.htm
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This was so far the dev/inactive and the dev/active part.
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I have written a small servlet which is mainly used to communicate via different types of clients using http.
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Release resource

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