Re: Using POI to create XLS from a C app

Rob Y. wrote:
You can call C->Java via JNI.

It is a bit of work, but not that much worse than what you have
already coded.

Sounds interesting. What I don't get is that, presumably POI needs to
be instantiated and remain so for the duration of the process. If I
had a C app calling into POI via JNI, would that be possible? I guess
I'm assuming JNI needs to embed the Java interpreter in your C app (or
dynamically link to it), and that each Java call would encapsulate a
complete instance of the Java environment, which would have to clean
itself up upon completion of the JNI call.

Maybe it's more flexible than that? (actually, I always thought JNI
was to allow Java to call out to C, so maybe there's a lot more to it
than I know about)

JNI can also be used to call Java from C.

You can start the JVM and create objects that you can keep
over multiple invocations.

I can create a simple example if needed.

Arne
.

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