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Sharing Objects between Webapps

Stephen Callaghan

Joined: Feb 26, 2002
Posts: 12
I'm trying to allow one webapp in its own Context to reference an objects instance in another webapp (within the same tomcat container).
I've tried singleton pattern (since i thought it was the same VM it would be shared) and I've tried binding it to JNDI but no luck. The second webapp can never see the first live instance (i tried crossContext="true" in both Context tags too but no luck).
Do i have to go down the RMI or EJB route to achieve what I want? Its not that big a project and i'm not sure if i could sell the investment in time setting that up to the company.
Any help or pointers much appreciated.
btw, its an Admin Type webapp that is trying to see into the other webapps to display current status information for some specific information and allow operations like start/stop on a couple of objects.

==========================<br />Stephen Callaghan<br />SC Java Programmer<br />SC Java Developer<br />SC Web Component Developer<br />SC Enterprise Architect I
Karthik Guru
Ranch Hand

Joined: Mar 06, 2001
Posts: 1209
W'd it work if the singleton is packaged in a jar and kept inside the shared common\lib folder of tomcat? I mean all the webapps s'd be able to see the single instance of this class.
If we have one classloader/webapp guess the singleton class will get loaded as many times even though it lies in the same JVM.
Stephen Callaghan

Joined: Feb 26, 2002
Posts: 12
Of course!!!
Couldnt understand why the singleton wouldnt work but it is indeed the classloaders. Have put common code under "common/lib" and removed from individual web apps and it works perfectly. I guess thats why they call it "common"!!
Thanks so much for your help in this.
I agree. Here's the link:
subject: Sharing Objects between Webapps
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