import com.apple.laf.AquaImageFactory.SlicedImageControl; //导入依赖的package包/类
@Override
void paint(final Graphics2D g, final T stateToPaint) {
    if (metricsProvider == null) {
        AquaSingleImagePainter.paintFromSingleCachedImage(g, control, stateToPaint, boundsRect);
        return;
    }

    RecyclableJRSUISlicedImageControl slicesRef = slicedControlImages.get(stateToPaint);
    if (slicesRef == null) {
        final NineSliceMetrics metrics = metricsProvider.getNineSliceMetricsForState(stateToPaint);
        if (metrics == null) {
            AquaSingleImagePainter.paintFromSingleCachedImage(g, control, stateToPaint, boundsRect);
            return;
        }
        slicesRef = new RecyclableJRSUISlicedImageControl(control, stateToPaint, metrics);
        slicedControlImages.put(stateToPaint, slicesRef);
    }
    final SlicedImageControl slices = slicesRef.get();
    slices.paint(g, boundsRect.x, boundsRect.y, boundsRect.width, boundsRect.height);
}
 

import com.apple.laf.AquaImageFactory.SlicedImageControl; //导入依赖的package包/类
SlicedShadowBorder(final Painter prePainter, final Painter postPainter, final int offsetX, final int offsetY, final float distance, final float intensity, final int blur, final int templateWidth, final int templateHeight, final int leftCut, final int topCut, final int rightCut, final int bottomCut) {
            super(prePainter, postPainter, offsetX, offsetY, distance, intensity, blur);

            final BufferedImage i = new BufferedImage(templateWidth, templateHeight, BufferedImage.TYPE_INT_ARGB_PRE);
            super.paintBorder(null, i.getGraphics(), 0, 0, templateWidth, templateHeight);
//            debugFrame("slices", i);
            slices = new SlicedImageControl(i, leftCut, topCut, rightCut, bottomCut, false);
        }