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jnlpappletlauncher w/ jogl working on windows?

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2 replies [Last post]
Joined: 2011-01-31

I'm interested in java applets w/ opengl so I looked into jogl and came upon jnlpappletlauncher. So I attempted to view this site:
On Mac, it works fine under both Safari and Firefox. On Windows Vista, I get "Error: Class Not Found: demos.applets.GearsApplet" whether I am using Firefox, Chrome, or IE.
Is this a OS dependent issue? Is there something I did not install in Windows?
I feel this should be a common problem, but a google search was not insightful.
Thank you for any help you can provide.

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Joined: 2010-08-10

Huh, I get this on Windows 7, 64-bit, JRE 6_24:

java.lang.ClassNotFoundException: demos.applets.GearsJOALApplet
    at sun.plugin2.applet.Applet2ClassLoader.findClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass0(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
    at sun.plugin2.applet.Plugin2ClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Unknown Source)
    at org.jdesktop.applet.util.JNLPAppletLauncher.startSubApplet(

I'm assuming we're talking about . Same result in IE and Firefox.

Joined: 2004-07-13

Since upgrading my JRE to JRE1.6.0_10 version and beyond, up to JRE1.6.0_23 version, I have been unable to run my Applets in any browser on my 32bit Windows VISTA system. The error message I get is "Error: Class not found". The class referred to is the Applet's main class.
I am using JNLP and the JNLPAppletLauncher to load additional library JARs at runtime, specifically Java3D and JOGL amongst others.
From my research on many different forums now and some experimentation, I have found the problem appears to be directly associated with these later updates of the JRE.
I understand these updates of the JRE run the Applet in its own process, for several obvious benefits, and that this is what is interfering with the JNLPAppletLauncher's ability to find and load the main class.
I get the same error in FireFox, IE, Opera, SeaMonkey and Google Chrome browsers. However, the Applets run fine in the Apple Safari browser.
To confirm that this problem is not just related to the way I am embedding my Applets, I get exactly the same results with the JOGL/JOAL Applet Test at
If I switch off the "Next Generation Java Plugin", all of the Applets then run successfully in the IE browser under JRE1.6.0_23 but continue to fail in the remaining (Mozilla and Chrome) browsers.
If I revert to a pre-JRE1.6.0_10 version (JRE1.6.0_07), the Applets all run successfully in all of the browsers.
Even if switching off the "Next Generation Java Plugin" solved the problem on all browsers, it is not feasible for me to ask all my clients to do so (even if they do have Administrator permissions) and it is definitely not feasible for me to ask them to downgrade their JRE installation to JRE1.6.0_07, even if they did understand what that means.
As this problem has clearly been documented in many different flavours on your forum as well as many others across all of the JRE updates since JRE1.6.0_10, I would hope you would have a solution to it by now. I have been unable to find a solution in all my research to date.
Is there a documented method of embedding the Applet code in the HTML that will work with JNLPAppletLauncher and JRE1.6.0_23?
I am currently using:

<br />

<applet code="org.jdesktop.applet.util.JNLPAppletLauncher"
<param name="codebase_lookup" value="false"><param name="subapplet.classname" value="com.iq2tech.model.Iq2model">
<param name="subapplet.displayname" value="Running 3D Viewer Applet">

<param name="jnlpNumExtensions" value="2">
<param name="jnlpExtension1" value="">
<param name="jnlpExtension2" value="">

Thank you in advance for any help you can give me in this urgent matter.
Kind regards