[JAVA] Linien zeichnen, 2D Array

import java.awt.*;
import java.awt.event.*;


public class Linien extends Frame {

  public Linien(String title) {
    super(title);
    addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent evt) { dispose(); }
    });
    addMouseListener(new MyMouseListener());
    int frameWidth = 300;
    int frameHeight = 300;
    setSize(frameWidth, frameHeight);
    Dimension d = Toolkit.getDefaultToolkit().getScreenSize();
    int x = (d.width - getSize().width) / 2;
    int y = (d.height - getSize().height) / 2;
    setLocation(x, y);
    setResizable(false);
    setVisible(true);
  }

  public static void main(String[] args) {
    new Linien("Linien");
  }

  private int[][] koordinaten = new int[1024][4];

  private int x = 0;
  private int y = 0;
  private int x2 = 0;
  private int y2 = 0;

  private boolean clicked = false;

  private int linien = 0;

  public void paint(Graphics g){
    for(int i = 0;i <= linien;i++){
        g.drawLine(koordinaten[i][0],koordinaten[i][1],koordinaten[i][2],koordinaten[i][3]);
    }
  }


  public class MyMouseListener extends MouseAdapter{
    public void mouseClicked(MouseEvent event){
       if (!clicked){
          x = event.getX();
          y = event.getY();
       }
       else{
          x2 = event.getX();
          y2 = event.getY();
          koordinaten[linien][0] = x;
          koordinaten[linien][1] = y;
          koordinaten[linien][2] = x2;
          koordinaten[linien][3] = y2;
          linien++;
       }
       clicked = !clicked;
       repaint();
    }
  }


}