public static final URL ICON16 = HelperUi.class.getResource("/com/jsql/view/swing/resources/images/software/bug16.png");
public static final URL ICON32 = HelperUi.class.getResource("/com/jsql/view/swing/resources/images/software/bug32.png");
public static final URL ICON96 = HelperUi.class.getResource("/com/jsql/view/swing/resources/images/software/bug96.png");

List<Image> images = new ArrayList<>();
try {
    images.add(ImageIO.read(HelperUi.ICON96));
    images.add(ImageIO.read(HelperUi.ICON32));
    images.add(ImageIO.read(HelperUi.ICON16));
} catch (IOException e) {
    LOGGER.error(e, e);
}

// Define a small and large app icon
this.setIconImages(images);