Question about multiple servlet comms

all,
Ok here is the setup:
Let�s say I have 3 servlets (A, B, C)
A is started and then responsible for polling a database to check for updates since last poll until it is destroyed on server shutdown
B is an intermediary servlet
C is responsible for pushing data to the client�s that have subscribed
The problem is this:
A is invoked and begins periodically checking a DB for updated data. Upon finding updated data it should forward the data to B. This does some checking and then in turn forwards the updated data to C. C then formats the data and pushes it to the client�s browser where it is displayed as SVG.
I am thinking B->C could simply be resolved through the use of a request dispatcher.
However the problem lies in the communication of A->B.
Since servlet A should frequently (once a sec) poll and check the database contents to see if it has been updated I thought an easy way to do this would be to have the servlet make its check; if nothing has changed redirect the response back to itself. If there has been a change, update servlet B with that change. The problem is how can one send the update to servlet B without halting servlet A�s cycle?
If I open a httpURL connection to B then A will wait for B to pass a response back, but B wants to forward the request, via request dispatcher to C after some processing. Therefore A will hang as no response from B will be written.
If I have A use a request dispatcher to forward the data to B I am unable to redirect the response back to A and thus have it continuously checking.
Unfortunately it is unlikely I can make any changes to the architecture. Any ideas?
Kind regards

Sorry I can't help but I am interested in a similar problem.
Anyone out there?

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</web-app>Now, once the container starts (Tomcat?), you should be able to see that servlet in:
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>
>> there are two
>> root directories on the server: public_html and www
>>
>
> Usually, only one of them is a real folder. The other is
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