import java.awt.*;
import javax.swing.*;

public class Stapel extends JPanel {

  private double procent;

  @Override
  public void paintComponent(Graphics g) {
    super.paintComponent(g);
    g.setColor(getForeground());
    int höjd = (int) (getHeight() * procent /100);
    g.fillRect(0, getHeight()- höjd, getWidth(), höjd);
  }

  public void sättProcent(double p){
    if (p >= 0 && p <= 100)
      procent = p;
    else 
      throw new IllegalArgumentException("Felaktigt argument");
    repaint();
  }
}