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The moose likes Servlets and the fly likes Servlet Filter Big Moose Saloon
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Servlet Filter

Rajeev Iyer
Ranch Hand

Joined: Jun 19, 2002
Posts: 42
What is a Servlet Filter ?
How and why would one need it ?
Thanks ......
Frank Carver

Joined: Jan 07, 1999
Posts: 6920
A servlet filter is a chunk of code that gets executed for every request (or response) that it is mapped to. For example, you might map a filter to all requests for URLs matching /private/* which checks whether the requester has logged in and is authorized to see the resource.

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Ken Robinson
Ranch Hand

Joined: Dec 23, 2003
Posts: 101
You can only map a URL to one Servlet.
You can map a URL to multiple Filters.
As stated above, this allows you to place code that is very common in a Filter and map which URLs you want it to apply to. You only write the code once. If you wanted this without Filters, you would have to put the same code or method call in each and every place you wanted and recompile.
Rajeev Iyer
Ranch Hand

Joined: Jun 19, 2002
Posts: 42
Thanks for the replies...
Could you please suggest any site where I can view some example code ?
I agree. Here's the link:
subject: Servlet Filter
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