code: public static BufferedImage copyImage(Image img, int imageType) {
  		final BufferedImage bimage = new BufferedImage(img.getWidth(null), img.getHeight(null), imageType);
  		final Graphics2D bGr = bimage.createGraphics();
  		bGr.drawImage(img, 0, 0, null);
  		bGr.dispose();
  
  		return bimage;
  	}
docs: 将已有Image复制新的一份出来
  
  @param img {@link Image}
  @param imageType {@link BufferedImage}中的常量，图像类型，例如黑白等
  @return {@link BufferedImage}
  @see BufferedImage#TYPE_INT_RGB
  @see BufferedImage#TYPE_INT_ARGB
  @see BufferedImage#TYPE_INT_ARGB_PRE
  @see BufferedImage#TYPE_INT_BGR
  @see BufferedImage#TYPE_3BYTE_BGR
  @see BufferedImage#TYPE_4BYTE_ABGR
  @see BufferedImage#TYPE_4BYTE_ABGR_PRE
  @see BufferedImage#TYPE_BYTE_GRAY
  @see BufferedImage#TYPE_USHORT_GRAY
  @see BufferedImage#TYPE_BYTE_BINARY
  @see BufferedImage#TYPE_BYTE_INDEXED
  @see BufferedImage#TYPE_USHORT_565_RGB
  @see BufferedImage#TYPE_USHORT_555_RGB