How to create a JVM in native code and call a Java Method from a Java Class?

[Lavakush Verma]

Dear All !

I am trying to call a java method from native code (C/C++), to which i ll need the instance of JVM at Native code. but i am unable to get success regarding that issue. The scenario is like..

I have a c code running, within main() function i need to call the java method based on some conditions. when i m trying to create the JVM at main() function before the Java method call it is not even compiling successfully.

Error : createJVM.c:18: undefined reference to `JNI_CreateJavaVM'
collect2: ld returned 1 exit status

//////CreateJVM.c

#include <stdio.h>
#include <jni.h>

JNIEnv* create_vm() {
	JavaVM* jvm;
	JNIEnv* env;
	JavaVMInitArgs args;
	JavaVMOption options[1];

	/* There is a new JNI_VERSION_1_4, but it doesn't add anything for the purposes of our example. */
	args.version = JNI_VERSION_1_6;
	args.nOptions = 1;
	options[0].optionString = "-Djava.class.path=d:\\javaprg";
	args.options = options;
	args.ignoreUnrecognized = JNI_FALSE;

	JNI_CreateJavaVM(&jvm, (void**)env, &args);
	return env;
}

void invoke_class(JNIEnv* env) {
	jclass helloWorldClass;
	jmethodID mainMethod;
	jobjectArray applicationArgs;
	jstring applicationArg0;

	helloWorldClass = (*env)->FindClass(env, "MyJavaProgram");

	mainMethod = (*env)->GetStaticMethodID(env, helloWorldClass, "main", "([Ljava/lang/String;)V");

	applicationArgs = (*env)->NewObjectArray(env, 1, (*env)->FindClass(env, "java/lang/String"), NULL);
	applicationArg0 = (*env)->NewStringUTF(env, "From-C-program");
	(*env)->SetObjectArrayElement(env, applicationArgs, 0, applicationArg0);

	(*env)->CallStaticVoidMethod(env, helloWorldClass, mainMethod, applicationArgs);
}


int main(int argc, char **argv) {
	JNIEnv* env = create_vm();
	invoke_class( env );
}

i am putting my source code here..
please help me. I am an urgent need to solve this issue...

Regards,

LK

[Lavakush Verma]

Dear Friends,
I have also tried help from this link..
but could not succeed to compile my C Code.

http://www.codeproject.com/KB/cpp/CJniJava.aspx

Regards,
Lavakush