class Mapa extends JPanel {
    private BufferedImage obrazekMapy; 
    
    public Mapa(BufferedImage obrazekMapy) {
      this.obrazekMapy = obrazekMapy;
    }

    public Mapa(String soubor) {
      obrazekMapy = ImageIO.read(new File(soubor));

    }
    
    @Override
    public Dimension getPreferredSize() {
        return new Dimension(obrazekMapy.getWidth(), obrazekMapy.getHeight());
    }

    @Override
    protected void paintComponent(Graphics g) {
      super.paintComponent(g);
      g.drawImage(obrazekMapy,0,0,null);  
    }

}