Preserving session with JNI

I'm working on an application for interacting with a database, the database has a Java API and a C API for some of the backend functions. I'd like to use some of the C API for the backend to improve the performance of the application. The problem is that I can't pass the connection information back and forth between the Java side and the C side. The connection sessions are maintained by objects in either API (a Java class for connections and a C class for connections). These classes aren't identical, but they're very similar.
I'm not very experienced with JNI, but as far as I've read/tried, I can't pass these objects back and forth between Java and C. Since JVM addressing isn't necessarily absolute, I can't rely on getting an address to reference on the C side, and since (as far as I'm aware) I can only instantiate a Java side connection with Java side methods, I can't refer to a connection from the C-side either.
Long story short, I'm stuck trying to find a way to make these 2 API's get along so that I can get the added performance of the C backend. For some reason the API's don't have any methods that use session ID's or anything else that would be useful for this sort of thing. Maybe there is something else I could try or maybe I'm just missing something (it wouldn't be the first time).
Any thoughts/ideas/suggestions would be much appreciated.

nsop07 wrote:
I'm working on an application for interacting with a database, the database has a Java API and a C API for some of the backend functions. I'd like to use some of the C API for the backend to improve the performance of the application. And why do you think that will work?
The problem is that I can't pass the connection information back and forth between the Java side and the C side. The connection sessions are maintained by objects in either API (a Java class for connections and a C class for connections). These classes aren't identical, but they're very similar.
I'm not very experienced with JNI, but as far as I've read/tried, I can't pass these objects back and forth between Java and C. Since JVM addressing isn't necessarily absolute, I can't rely on getting an address to reference on the C side, and since (as far as I'm aware) I can only instantiate a Java side connection with Java side methods, I can't refer to a connection from the C-side either.
In java you perserve a pointer, any pointer, via a java long value. Cast it back and forth when you go back and forth.
Don't forget to provide a mechanism to clean it up.
Java objects are similar and well defined in JNI - you pass a reference and access it via JNI methods.

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You cannot shadow a session with multiple monitors enabled in Windows Server 2008 R2

Searching through the forums (and according to KB2484290) it appears that there is no solution to this problem. We are rolling out thin clients that are using dual monitors exclusively and we were very surprised to find out that we couldn't shadow
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Preserving session with JNI

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