How to run a Java applet in the browser: "Class Not Found exception"

Question

I'm trying to get a Java applet to display in the browser - I know this question has been asked a number of times but I can't seem to find the answer that works specifically for this case - over the past few days I've tried everything from moving the HTML file to various places in the directory structure to using <applet> vs. the deployJava() API.

The code runs fine as a standalone applet in Eclipse, but when I try to run it in the browser I get either a "ClassNotFound" or "ClassDefNotFound" exception. I've packaged the code into a .jar and placed the .jar within the same folder as the HTML file, with my java code as follows:

package myPackage;
import java.awt.*;
import java.applet.*;

public class myClass extends java.applet.Applet{
    public void init(){
        String latLong = getParameter("unUsedParameter");
    }

    public void paint(Graphics g){
        g.drawString("Hello World",50,25);
    }
}

and the Javascript code is as follows:

<script src="https://www.java.com/js/deployJava.js"></script>
<section id = "java">
    <script type="text/javascript">
        var attributes = {
            code:'myClass.class',
            archive: 'myApplet.jar',
            width:500, height:500
        };
        var parameters = {latLong: total_path}; 
        var version = '1.8'; 
        deployJava.runApplet(attributes, parameters, version);
    </script> 
</section>

I also tried using codebase: 'myApplet.jar' instead of archive: but that didn't work either - I keep getting one of the same two exceptions. HELP!

EDIT: First off, the code: attribute was incorrect in my original post, it should have read 'myClass.class' (this is corrected above). The answer that got it working was changing the code: attribute to code: 'myApplet/myClass' - thanks for your help!

Answer 1

Change your 'code' parameter to 'myPackage.myClass', instead of 'myApplet.class'.

You have more insights about the declaration in this post, which I've shown a way that works Angular.js and Java Applet

ie:

<script>
    <!-- applet id can be used to get a reference to the applet object -->
    var attributes = { id:'cdigApplet', code:'cdig.CDigApplet', archive:'cdig-applet-1.0.jar', width:1, height:1, classloader_cache:'false'} ;
    var parameters = {persistState: false, cache_option:'no' } ;
    deployJava.runApplet(attributes, parameters, '1.8');
</script>

My Applet

package cdig;

import java.applet.Applet;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Base64;


/**
 *
 * @author Ulysses Marins 
 */
public class CDigApplet extends Applet
{

    private static final long serialVersionUID = 1L;

    String ret;

    CDigApplet applet = this;

    @SuppressWarnings({ "rawtypes", "unchecked" })
    public String signFile(String fileID, String pin, String token)
    {
        AccessController.doPrivileged(new PrivilegedAction()
        {
            @Override
            public Object run()
            {
                try
                {
                    File objFile = new File(token);

                    System.out.println("Iniciando processo de assinatura.");

                    objFile.sign("json", sig);

                        System.out.println(ret);
                    } else {
                        throw new IllegalArgumentException("Não foi possível iniciar processo de assinatura.");
                    }

                }
                catch (Exception e)
                {
                    String sl = "{\"success\":false," + "\"message\":\"" + e.getMessage() + "\"}";
                    ret = sl;
                    System.out.println(sl);
                }

                return null;
            }
        });

        return ret;
    }

    public void init(){
    }

    public void destroy(){
    }

}