Buffer JNA issue

gistfile1.java

// C++ header

extern "C" __declspec(dllexport) int __stdcall API_USBMF_Request(

                                                   HANDLE commHandle, int DeviceAddress, 

                                                   unsigned char inf_mode, unsigned char *Buffer);

// Java - Returns a single byte, which I think is a valid result

public int API_USBMF_Request(HANDLE commHandle, int DeviceAddress, char inf_mode, ByteByReference Buffer);

// Java - No change to byte array

public int API_USBMF_Request(HANDLE commHandle, int DeviceAddress, char inf_mode, byte[] Buffer);

Not sure about JNA, but if I was mapping the function with HawtJNI it would look like this:

public static final native int API_USBMF_Request(
        @JniArg(cast="HANDLE", flags={POINTER_ARG}) long commHandle, 
        int DeviceAddress,
        char inf_mode,
        @JniArg(cast="char *") byte [] Buffer);

Data get copied out the java objects and then back by default. But if you know that the Buffer is write only, the you can optimize by adding the NO_IN flag:

@JniArg(cast="char *", flags={NO_IN}) byte [] Buffer

I just tried using PointerByReference, and that appears to kind of give me something. If i toString the Pointer i get a nice native@0x123456 kinda thing, so i just need to work out how to to the Pointer equivalent of Native.toString(byte[] blah)

Not sure what the jna ByReference does, but byte[] definitely doesn't work

Any ideas why using Pointer.getString() failed with access exception, weridly using IntByReferernce returns values, though quite what this number is when what I want is a String I'm not sure. Some native thing ?