xhtml - ClassNotFoundException in Java Applet using <object> tag

Question

I'm trying to embed a Java Applet using the <OBJECT> tag, which is the XHTML Strict way of doing it.

After browsing lots of sites, I tried this example which seems to work pretty well:

<!--[if !IE]> Firefox and others will use outer object -->
  <object classid="java:Sample2.class" 
          type="application/x-java-applet"
          archive="Sample2.jar" 
          height="300" width="450" >
    <!-- Konqueror browser needs the following param -->
    <param name="archive" value="Sample2.jar" />
  <!--<![endif]-->
    <!-- MSIE (Microsoft Internet Explorer) will use inner object --> 
    <object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93" 
            codebase="http://java.sun.com/update/1.5.0/jinstall-1_5_0-windows-i586.cab"
            height="300" width="450" > 
      <param name="code" value="Sample2" />
      <param name="archive" value="Sample2.jar" />
      <strong>
        This browser does not have a Java Plug-in.
        <br />
        <a href="http://java.sun.com/products/plugin/downloads/index.html">
          Get the latest Java Plug-in here.
        </a>
      </strong>
    </object> 
  <!--[if !IE]> close outer object -->
  </object>
  <!--<![endif]-->

I downloaded that Sample2.jar and works perfectly on localhost.

Now, I replaced Sample2.class for the one I need to use (ar.uba.exactas.infovis.ivides.Scatterplot.class) and using my own JAR files (archive="piccolo.jar piccolox.jar netscape.jar scatterplot.jar"):

<!--[if !IE]> Firefox and others will use outer object -->
<object
    classid="java:ar.uba.exactas.infovis.ivides.Scatterplot.class"
    type="application/x-java-applet"
    archive="piccolo.jar piccolox.jar netscape.jar scatterplot.jar"
    height="300" width="450" >
    <!-- Konqueror browser needs the following param -->
    <param name="archive" value="piccolo.jar piccolox.jar netscape.jar scatterplot.jar" />
<!--<![endif]-->
    <!-- MSIE (Microsoft Internet Explorer) will use inner object -->
    <object classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
                    codebase="http://java.sun.com/update/1.5.0/jinstall-1_5_0-windows-i586.cab"
                    height="300" width="450" >
        <param name="code" value="ar.uba.exactas.infovis.ivides.Scatterplot" />
        <param name="archive" value="piccolo.jar piccolox.jar netscape.jar scatterplot.jar" />
        <strong>
            This browser does not have a Java Plug-in.
            <br />
            <a href="http://java.sun.com/products/plugin/downloads/index.html">
                Get the latest Java Plug-in here.
            </a>
        </strong>
    </object>
<!--[if !IE]> close outer object -->
</object>
<!--<![endif]-->

After doing so, I'm gettin this log dump:

java.lang.ClassNotFoundException: ar.uba.exactas.infovis.ivides.Scatterplot.class
    at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadCode(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager.createApplet(Unknown Source)
    at sun.plugin2.applet.Plugin2Manager$AppletExecutionRunnable.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.io.IOException: open HTTP connection failed:http://localhost/infovisUBA/2008-2C/tpfinal/bin/ar/uba/exactas/infovis/ivides/Scatterplot/class.class
    at sun.plugin2.applet.Applet2ClassLoader.getBytes(Unknown Source)
    at sun.plugin2.applet.Applet2ClassLoader.access$000(Unknown Source)
    at sun.plugin2.applet.Applet2ClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    ... 7 more
Excepción: java.lang.ClassNotFoundException: ar.uba.exactas.infovis.ivides.Scatterplot.class

The only difference I see is that I'm using a class inside a package.

Also, please note I did make this work using the <APPLET> tag, but I cannot make it with <OBJECT>.

Any clue?

Answer 1

Have you by any chance written this:

<param name="code" 
       value="ar.uba.exactas.infovis.ivides.Scatterplot.class" />
<param name="archive"
       value="piccolo.jar piccolox.jar netscape.jar scatterplot.jar" />

instead of:

<param name="code"
       value="ar.uba.exactas.infovis.ivides.Scatterplot" />
<param name="archive"
       value="piccolo.jar piccolox.jar netscape.jar scatterplot.jar" />

The difference is the lack of ".class" at the end of the code value. Judging by the example, it should be at the end of the classid attribute, but not at the end of the value for the code param.

That's what the stack trace suggests to me:

Excepción: java.lang.ClassNotFoundException: 
    ar.uba.exactas.infovis.ivides.Scatterplot.class

I wouldn't expect to see the ".class" at the end of the class name.