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



public class MyPanel extends JPanel
{
    public boolean linie = false; 
    public boolean kreis = false;
    int x = 100; 
    int y = 100000000;
    @Override
    protected void paintComponent(Graphics g){
        super.paintComponent(g);

        if (linie) g.drawLine(20,20,200,50);
        if (kreis) g.drawOval(50, 50, 30, 30);

    }
}