I try launch Applet in browser, but it is now working.
In AppletViewer everything is ok.
I coppied file .html to scr folder, and try to open them, I get a `ClassNotFoundException` saying that `PlanZajecJavaProjektApplet.class` can't be found:

![enter image description here](https://i.stack.imgur.com/kE4QX.jpg)

Code from html file

```
<HTML>
<HEAD>
   <TITLE>Applet HTML Page</TITLE>
</HEAD>
<BODY>

<H3><HR WIDTH="100%">Applet HTML Page<HR WIDTH="100%"></H3>

<P>
<APPLET codebase="classes" code="PlanZajecJavaProjektApplet.class" width=350 height=200></APPLET>
</P>

<HR WIDTH="100%"><FONT SIZE=-1><I>Generated by NetBeans IDE</I></FONT>
</BODY>
</HTML>

```

Code from java file:

```
import java.awt.GridBagConstraints;
import java.lang.reflect.InvocationTargetException;
import javax.swing.JButton;
import javax.swing.JTextArea;

public class PlanZajecJavaProjektApplet extends javax.swing.JApplet {
...

```