Loading lib per object and not per class possible?

Question

Hello, I have a problem with JNI and some libs I want to use.
On the Java side I have a class called FeedController that uses a class SenderJNI to communicate with a native lib, that implements the interface of SenderJNI. I have several native libs that all have different implementations of the interfaces.
What I want to do is to load a specific native lib for a specific SenderJNI object. I thought it could work with the following code.
public class SenderJNI {
     public native void init(String host, int port, String streamname);
     public native void send(String csvString);
     public native void close();
     public SenderJNI(String libName) {
           Runtime.getRuntime().load(libName);
}The problem I've encountered is, that loading libA.so for SenderJNI object A works fine, but if I want to load libB.so for SenderJNI object B, I still get the implementation of libA.so. So loading seems to be on a class based level.
Is there any way to load those two libs for different SenderJNI objects?

Answer 1

This might work.
Load all three libraries in your SenderJNI. Create three sub classes of your SenderJNI java class. They can just be stubs that dont implement anything.
Implement the native methods just once between the three libraries.
In your navtive methods, use IsAssignableFrom to determine which instance of the class was used, and call the proper library function based on the instance type that the call originated from.
jboolean IsAssignableFrom(JNIEnv *env, jclass clazz1,jclass clazz2);