Storing references in records

[Neiko2002]

It should be possible to store references to other Java objects in a record.

interface ImageData {
    @Reference
    public BufferedImage getImage();
    public void setImage(BufferedImage image);
}

The generated source should look like this

public class ImageDataRecord implements ImageData {
    public static BufferedImage[] images;
    public BufferedImage getImage() {
        return images[index()];
    }
    public void setImage(BufferedImage image) {
        images[index()] = image;
    }

    // these functions will be added if a reference is needed somewhere in the record
    public void init(int index) {
        memory.setInt(address(), index);
    }

    public int index() {
        return memory.getInt(address());
    }

    public static void ensureCapacity(int size) {
        images = new BufferedImage[size];
    }

    public void release() {
        images[index()] = null;
    }
}

The init function gets called every time a record is allocated. The passed index is handled by the RecordAdapter ensuring it is not used by another record of this type. The capacity of the underlying array gets increased by the adapter with a step size of 16. Release() will also be called by the adapter.

This features needs a lot of managing functions in order to be fast, a simple but slow version could look like this.

public class ImageDataRecord implements ImageData {
    public static Map<Long, BufferedImage> images = new HashMap<>();
    public BufferedImage getImage() {
        return images.get(address());
    }
    public void setImage(BufferedImage image) {
        images.put(address(), image);
    }

    // these functions will be added if a reference is needed somewhere in the record
    public void release() {
        images.remove(address());
    }
}