try
{
    image = ImageIO.read(Images.class.getResourceAsStream(imageName));
    BufferedImage img = new BufferedImage(image.getWidth(), image.getHeight(), BufferedImage.TYPE_INT_ARGB);
    Graphics g = img.getGraphics();
    g.drawImage(image, 0, 0, null);
    g.dispose();
    image = img;
}
catch (IOException e)
{
    e.printStackTrace();
    return null;
}

this.getClass().getResource("/resource/buttons1.png")

this.getClass().getResourceAsStream("/resource/TX_Jello2.ttf")

Images.class.getResourceAsStream("/" + fileName)