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variable doesn't increment

 
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this is my web.xml


this is my jsp


i need to increment the value printed each time when i type this on broser
http://localhost:8080/test/
but it always gives 1.
why the count variable doesn't increment.
 
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Because you all the time declare it as zero?
 
anarkali perera
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then what i have to change
 
anarkali perera
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i need to declare count when each time the web browser hit it should increment the value.how should i declare it
?
 
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How did you check this ? Tried refreshing the page?
 
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Check out the concept of the application context, and how you can use it to store values (called "attributes") throughout the application lifetime.
 
anarkali perera
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yes .i need to increment when refreshing?
 
Vijitha Kumara
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anarkali perera wrote:yes .i need to increment when refreshing?


If you want this available to the whole appplication use javax.servlet.ServletContext or to a particular session use javax.servlet.http.HttpSession. The code you have given work only for that particulr jsp/URL.
 
anarkali perera
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i change the web.xml

<context-param>
<param-name>var</param-name>
<param-value>1</param-value>
</context-param>

and i change the jsp

but it gives
The page var is now: null
why it gives null?
 
Ulf Dittmer
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Context init parameters are not the same thing as context attributes. In particular, context init parameters are immutable, so you can't use them for what you want to do (except for fetching an initial value with which to seed the attribute).
 
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You can do this very easily using a servlet :

declare a variable



then in servlet's doGet method write :




And in jsp, write,



 
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buddy
may there is some other problem with your system but the value is increasing for me..i have copy pasted your program in my tomcat and while refreshing (internet explorer) the value is increasing as it should be.

and the variable declared in (Declaration Tag) <%! %> are same as to those which are declared at class level in case of servlets

 
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