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Trouble with JNI wrapper functions

Colby Nyce
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Hi all,

I am trying to call Java methods from C++ code using the JNI wrapper
functions that we have available in the "jmi" library, but I am having
difficulty figuring out how to obtain one of the required input variables.
I need to use any one of the "mljCall<type>Method" functions, such as:


These functions accept at least two parameters. The first is a "jobject",
and the second is a "jmethodID" (any additional arguments are treated as
input parameters to your Java method). I have been able to get an address
to my Java method, but I am not sure how to get an appropriate "jobject" to
use with this function. The code I have boils down to this:

/************************************************** ************************/
jclass objectClass = mljFindClass("WebScopeInterfaceToJava");
jmethodID webscopeMethod = mljGetMethod(objectClass, "voidMethod",
jobject j_obj = // How do I get this?
/************************************************** ************************/

Where do I get the correct "jobject" from? Is this available from the
global JVM or something? I have looked through a lot of the source code,
but I am finding it to be somewhat cryptic. Please bear with me, I am
completely new to JNI!


Reply With Quote
Roedy Green
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On Thu, 8 Sep 2011 15:10:06 -0400, "Colby Nyce" <(E-Mail Removed)>
wrote, quoted or indirectly quoted someone who said :

> Please bear with me, I am
>completely new to JNI!


Order a textbook.

Google the names of problematic methods. Looking at other people's
code will give you clues on how to use them.
Roedy Green Canadian Mind Products
The modern conservative is engaged in one of man's oldest exercises in moral philosophy; that is,
the search for a superior moral justification for selfishness.
~ John Kenneth Galbraith (born: 1908-10-15 died: 2006-04-29 at age: 97)
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