C ++ JNI互操作性

Question

After a thorough search of these forums, and being unable to find a relevant answer; I decided to ask you, the kind people of StackOverflow my question.

I currently have 3 (C++) libraries:

• StaticLib (containing pure virtual interfaces and "C" style prototypes)

• DynamicLibLinux (containing Linux implementation of above prototypes)

• DynamicLibAndroid (not sure what to put in here)

The problem is, I don't want to change the StaticLib's code which is:

struct IObject {
 virtual ~IObject() {}
 virtual void foo() = 0;
};

extern "C" { 
 IObject* CreateObject();
}

The DynamicLibLinux contains

#include <IObject.h>
class Object : public IObject {
public:
 virtual ~Object() {}
 virtual void foo() {
  //do something incredibly useful here...
 }
};

#ifdef __cplusplus
extern "C" {
#endif
IObject* CreateObject() {
 return new Object;
}
#ifdef __cplusplus
}
#endif

after which, in my linux standalone, I can call the dlsym("libDynamicLibLinux.so") function to load my CreateObject function. And it all works like a charm. Now, here's the thing: I want to use the static library in an Android application as well. And I can't figure out how to implement this in JNI. So far I have something like this:

#include <IObject.h>
#include <jni.h>
class Object : public IObject {
... same as above
};

#ifdef ...
JNIEXPORT IObject* JNICALL CreateObject(JNIEnv*) {
 return new Object;
}

which will, obviously, not work since the implementation doesn't match the declaration. So my question boils down to:

Is there any way I can use the C++ static lib "as-is" with JNI?

Kind regards and thank you for you patience,

Emiel

EDIT: In the meantime, i've found something promising: javacpp. Does anyone here have experience with using this library?

Answer 1

I'm not sure I understand how your system works, but yes something like this interface should work with JavaCPP :

@Platform(include="IObject.h",link="DynamicLib")
public class DynamicLib {
    public static class IObject extends Pointer {
        public native void foo();
    }
    public static native IObject CreateObject();
}