Re: C++ pointers in JNI

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#447

From: Kevin Dean [TeamB]
Date: Mon, 19 Sep 2005 04:19

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Salvador Huertas wrote:

>I need use a C++ library with Java, I read de JNI documentation but, I 
>don't find anything about pointers. My question is: If I have a C++ rutine 
>with a parameter of type "double *par1" or "int *par2", what's java type 
>that must I use in the function's declaration within the java wrapper?.

I have no direct experience with JNI but you'll likely have to create some 
kind of proxy method and a wrapper class for the types you're passing by 
address.  For example:

public class DoubleWrapper {
   public double value;
}

You would then pass a DoubleWrapper object into a JNI function, which 
would then pass the address for the value to the C++ function you're truly 
interested in.  Class objects are passed by reference in Java whereas 
native types are passed by value.

-- 
Kevin Dean [TeamB]
Dolphin Data Development Ltd.
http://www.datadevelopment.com/

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