jni methos in c++ class

[bharani rao]

hi,

I have a silly doubt, but it is worth so much for my project.

Is it possible to declare jni methods in c++ class...

till now i have jni with no c++ class

example

this is the java class

class testin {
      public native int Add(int a , int b);
	   public native int Sub(int a , int b);
	    public native int Mul(int a , int b);
		 public native int Div(int a , int b);
		  public native int Mod(int a , int b);

      static {
         System.loadLibrary("test");
      }
      public static void main(String[] args) {
        testin s = new testin();
		int v = s.Add(3,3);
		int va = s.Sub(3,3);
		int val = s.Mul(3,3);
		int valu = s.Div(3,3);
		int value = s.Mod(3,3);
		System.out.println("sum is " + v);
		System.out.println("diff is " + va);
		System.out.println("pro is " + val);
		System.out.println("quo is " + valu);
		System.out.println("rem is " + value);

      }
}

this is the c++ code. it has no class

#include "stdafx.h"

#include "testin.h"
#include "jni.h"

//using namespace System;

	JNIEXPORT jint JNICALL Java_testin_Add(JNIEnv *env, jobject obj, jint a, jint b)
	{
		return (a + b);
	}

	JNIEXPORT jint JNICALL Java_testin_Sub(JNIEnv *env, jobject obj, jint a, jint b)
	{
		return (a - b);
	}

	JNIEXPORT jint JNICALL Java_testin_Mul(JNIEnv *env, jobject obj, jint a, jint b)
	{
		return (a * b);
	}
	JNIEXPORT jint JNICALL Java_testin_Div(JNIEnv *env, jobject obj, jint a, jint b)
	{
		return (a / b);
	}

	JNIEXPORT jint JNICALL Java_testin_Mod(JNIEnv *env , jobject obj, jint a, jint b)
	{
		return ( a % b);
	}

these (JNIEXPORT jint JNICALL Java_testin_Mod) are from the header file created from the java file...

now i have c++ class and i need jni to be integrated to some of the methods of that class. but it is thowing error from the java class where i call the c++ method...


any help please..

thanks in advance

[Rob Spoor]

Have you compiled the C++ file as a DLL file? Is that DLL file called test.dll? Is that DLL file in a folder in the java.library.path?

[bharani rao]

rob,

i'm workin in linux.
i created the so file..
placed that in /usr/lib<something> folder

when running i get these errors because there is a class in c++...

it is working fine if i place that JNIEXPORT etc., outside the class.