code: import java.io.IOException;
  import java.awt.Color;
  import java.awt.Point;
  import java.awt.image.BufferedImage;
  import java.io.File;
  import javax.imageio.ImageIO;
  
  public class Test {
    public Test() throws IOException {
      BufferedImage image = ImageIO.read(new File("Unfilledcirc.png"));
      new FloodFill().floodFill(image, new Point(50, 50), Color.WHITE, Color.RED);
      ImageIO.write(image, "png", new File("output.png"));
    }
  
    public static void main(String[] args) throws IOException {
      new Test();
    }
  }
  