app.cpp

Invoke JavaProg.main() from a win32 program: . compile Main.java . compile VC project . set include

// App.cpp : Defines the entry point for the application.
//

#include "stdafx.h"

#include <stdlib.h>
#include <jni.h>

#define PATH_SEPARATOR ';'

int APIENTRY WinMain(HINSTANCE hInstance,
                     HINSTANCE hPrevInstance,
                     LPSTR     lpCmdLine,
                     int       nCmdShow)
{
 	// TODO: Place code here.
    JNIEnv *env;
    JavaVM *jvm;
    JavaVMInitArgs vm_args;
    jint res;
    jclass cls;
    jmethodID mid;
    jstring jstr;
    jobjectArray args;

	JavaVMOption options[1];
	options[0].optionString = "-Djava.class.path=.";
	vm_args.version = 0x00010002;
	vm_args.options = options;
	vm_args.nOptions = 1;
	vm_args.ignoreUnrecognized = JNI_TRUE;
	/* Create the Java VM */
	res = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);

    if (res < 0) {
        fprintf(stderr, "Can't create Java VM\n");
        exit(1);
    }

    cls = env->FindClass("Main");
    if (cls == 0) {
        fprintf(stderr, "Can't find Prog class\n");
        exit(1);
    }
 
    mid = env->GetStaticMethodID(cls, "main", "([Ljava/lang/String;)V");
    if (mid == 0) {
        fprintf(stderr, "Can't find Main.main()\n");
        exit(1);
    }

    jstr = env->NewStringUTF("From C!");
//    jstr = (*env)->NewString(env, "\u4ece", 3);
    if (jstr == 0) {
        fprintf(stderr, "Out of memory\n");
        exit(1);
    }
    args = env->NewObjectArray(1, 
                        env->FindClass("java/lang/String"), jstr);
    if (args == 0) {
        fprintf(stderr, "Out of memory\n");
        exit(1);
    }
    env->CallStaticVoidMethod(cls, mid, args);

    jvm->DestroyJavaVM();

	return 0;
}