public byte[] takeScreenshot() throws IOException {
 TakesScreenshot takesScreenshot = (TakesScreenshot) driver;
 return takesScreenshot.getScreenshotAs(OutputType.BYTES);
}

public BufferedImage createElementImage(WebElement webElement)
 throws IOException {
 // 获得webElement的位置和大小。
 Point location = webElement.getLocation();
 Dimension size = webElement.getSize();
 // 创建全屏截图。
 BufferedImage originalImage =
  ImageIO.read(new ByteArrayInputStream(takeScreenshot()));
 // 截取webElement所在位置的子图。
 BufferedImage croppedImage = originalImage.getSubimage(
  location.getX(),
  localtion.getY(),
  size.getWidth(),
  size.getHeight());
 return croppedImage;
}