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The moose likes Servlets and the fly likes ServletConfig & Servlet Context Big Moose Saloon
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ServletConfig & Servlet Context

Ranch Hand

Joined: Nov 22, 2008
Posts: 18944
Hai all,
Can any body explain
i. what is the servletContext and what it contain?
ii. what is the ServletConfig and what it Used for ?
or pl. give some useful links
Thanks & Regards
Sudatta Gautham

Joined: Dec 06, 2001
Posts: 1
A ServletContext represents the context in a servlet container of a servlet instance operates. A servlet container can have several contexts (or web applications) at one time. Each servlet instance is running in one of these contexts. All servlets instances running in the same context are part of the same web application and, therefore, share common resources. A servlet accesses these shared resource (such as a RequestDispatcher and application properties) through the ServletContext object.
The same servlet can be used in several web applications at one time. In fact, this may be common if there is a generic controller servlet that can be configured at run time for a specific application. Then, you would have several instances of the same servlet running, each possibly having different configurations.
This is where the ServletConfig comes in. This object defines how a servlet is to be configured is passed to a servlet in its init method. Most servlet containers provide a way to configure a servlet at run-time (usually through flat file) and set up its initial parameters. The container, in turn, passes these parameters to the servlet via the ServetConfig.
(Source : )

Sudatta Gautham NS
Gerry Giese
Ranch Hand

Joined: Aug 02, 2001
Posts: 247
Quick question regarding ServletContext - I just used the Forte IDE which uses Tomcat as the servlet container. I noticed that the tool shows you a list of the contexts that are deployed. What really blew me away was that you could delete a context without stopping the server! If anyone is familiar with Tomcat, what state would that leave the container in? Would the next request rebuild the context, or fail completely? Is there a way to 'reset' the context back to it's initially created state?

CJP (Certifiable Java Programmer), AMSE (Anti-Microsoft Software Engineer)
Author of Posts in the Saloon
Ashik Uzzaman
Ranch Hand

Joined: Jul 05, 2001
Posts: 2373

Sudatta, thnx for a nice presentation.
And geril i think as tomcat was already initialized and running on RAM when u deleted the context, the change will effect after u restart the container/server...just my guess...

Muhammad Ashikuzzaman (Fahim)
Sun Certified Programmer for the Java� 2 Platform
--When you learn something, learn it by heart!

Ashik Uzzaman
Senior Software Engineer, TubeMogul, Emeryville, CA, USA.
I agree. Here's the link:
subject: ServletConfig & Servlet Context
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