public void trackHexImages(IHex hex, MediaTracker tracker) {
public synchronized void trackHexImages(IHex hex, MediaTracker tracker) {
    public void trackHexImages(IHex hex, MediaTracker tracker) {        Image base = (Image)((Object[])hexToImageCache.get(hex))[0];        List superImgs = (List)((Object[])hexToImageCache.get(hex))[1];        // add base        tracker.addImage(base, 1);                // add superImgs        if (superImgs != null) {            for (Iterator i = superImgs.iterator(); i.hasNext();) {                tracker.addImage((Image)i.next(), 1);            }        }    }