Callback as parameter of C structure - Java wrapper generation

I have no problem with simple callbacks when free function passed as parameter to another, thanks to @flexo.

But assume bit more difficult C interface:

typedef struct
{
    int id;
    const char* name;
} Item;

typedef struct
{
    int value;
    Items_Callback callback;
    void *context;
} Items_Call;

typedef int (*Items_Callback)(const Item *item, void *context);

int Items_create(const Item *item, Items_Call *call) {
  ...
  call->callback(item, call->context);
  ...
}

I intent to generate some nice Java wrapper for code like this. I assume to have as result

class Item {
  public int id;
  public String name;
}

class Items_Call {
  public int value;
  public Object context;
  public Interface callback;
  public void setInterface(Interface i){ callback=i; };
}

public interface Interface {
  public int Items_Callback(Item item, Object context);
} 

int Items_create(Item item, Items_Call call) {
  ...
  call.callback.Items_Callback(item, call.context);
  ...
}

I realize that SWIG have some problem with generation of pure Java interfaces, but I believe it's not major problem. The problem is I have no idea how to reinterpret such nested structure to acceptable Java code.