Quadrat.java

import java.applet.Applet;
import java.awt.*;

public class Gitter extends Applet{
   public void paint(Graphics g){
      for (int x=0; x<=10;x++){
         g.drawLine(50+x*30,50,50+x*30,200);
      }
      for (int y=0;y<=5;y++){
         g.drawLine(50,50+y*30,350,50+y*30);
      }
   }
}

Quadrate.java

import java.applet.Applet;
import java.awt.*;

public class Quadrate extends Applet{
   public void paint(Graphics g){
      for (int x=50; x<=290;x+=30){
         for (int y=50;y<=170;y+=30){
            g.drawRect(x,y,26,26);
         }
      }
   }
}

Kreise.java

import java.applet.Applet;
import java.awt.*;

public class Kreise extends Applet{
   public void paint(Graphics g){
     for (int radius = 2; radius<=150;radius+=5){
       g.drawOval(180-radius, 180-radius, radius*2, radius*2);
     }
   }
}

Muster.java

import java.applet.Applet;
import java.awt.*;

public class Muster extends Applet{
   public void paint(Graphics g){
      for (int x = 30; x<= 280;x+=25){
         for (int y = 30; y<=155 ; y+=25){
            g.drawLine(x,y,x+20,y);
            g.drawLine(x+20,y,x+20,y+20);
            g.drawLine(x+20,y+20,x+5,y+20);
            g.drawLine(x+5,y+20,x+5,y+10);
            g.drawLine(x+5,y+10,x+10,y+10);
            g.drawLine(x+10,y+10,x+10,y+15);
            g.drawLine(x+10,y+15,x+15,y+15);
            g.drawLine(x+15,y+15,x+15,y+5);
            g.drawLine(x+15,y+5,x,y+5);
            g.drawLine(x,y+5,x,y+25);
         }
      }
   }