applet html problem, "class not found"

fromage

applet html problem, "class not found"

in Integration and Hardware • 3 years ago

hey there,

i am having trouble getting processing applets to work on my website.
i uploaded a couple of little sketches here:
http://www.generalzombie.de/sketchbook/sketchbook.php

when i open the applets there, they work for me. but my friends who tried to open them get a "class not found" error
concerning the main sketch class.
i did change the applet/index.html a little bit, but i did not edit the references. i only replaced the head <part> and took out the source code and processing link.
i implement the applet/index.html with the <iframe> tag, i dont know if that does anything to the references.
but then again, for me the references are all working, so it doesnt make any sense.
maybe i am missing something very obvious here.
the only guess i have left is that i maybe need to set the file authorization to allow "write" for everybody. unfortunately i cant just try that, because my ftp programm doesnt seem to let me alter that parameter.

thanks

Replies(5)

PhiLho

Re: applet html problem, "class not found"

3 years ago

Well, we don't have the source of your applets, so it is hard to tell.

Maybe you need to sign the applet, I think it is necessary for OpenGL applications, although I am not certain.

I also saw a thread about a similar error, where somebody tells there must be an empty constructor for the main class. Might be interesting to try if it is not done by the PDE.

fromage

Re: applet html problem, "class not found"

3 years ago

thanks phi.lho,

how can i create an empty constructor for the main class?
since processing is creating the main class by itself i don't know where i can do it.
the mainclass.java that is created however has no constructor in it.

i haven't yet tried to sign my applets. i thought this was not necessary,
because the users are asked for permission anyways before running it.
but i will wrap my head around this and give it a shot.
do you think the way it is described here is appropriate?
http://www.qoppa.com/faq/signapplet.htm

i found out in the meantime that there are some systems (including mine) that can
run the applets without the "class not found" error. i also made a try to set all the .jar references in the
index.html processing creates to absolute references, but that didnt have any effect whatsoever.

i have put back the code reference in this applet:
http://www.generalzombie.de/sketchbook/sketchbook.php?index=4#applet
maybe that helps

PhiLho

Re: applet html problem, "class not found"

3 years ago

saveFrame is definitively not OK in an applet...

And well, try and make a constructor of the name of your sketch. I don't guarantee it works, still worth a try.

fromage

Re: applet html problem, "class not found"

3 years ago

i took out saveFrame and added an empty constructor in some of the applets, but that did not help unfortunately :-(

i tested the applets on some more systems and i found out, that they work perfect on some systems (about 50%) and on others i get the class not found error. as far as i can tell this is not related to outdated browser or java versions on those systems.thsioth
this doesnt make any sense to me...

ochnoe

Re: applet html problem, "class not found"

2 years ago

same problem:
opengl sketch, works fine as sketch but not as applet -- P3D and an empty constructor didn't help :/

Java Plug-in 1.6.0_25
Verwendung der JRE-Version 1.6.0_25-b06 Java HotSpot(TM) Client VM
[...]
JNLPAppletLauncher: static initializer
os.name = windows vista
nativePrefix =   nativeSuffix = .dll
tmpRootDir = C:\Users\ochnoe\AppData\Local\Temp\jnlp-applet\jln4512532546995128764
Applet.init
subapplet.classname = parametrisch_3d_
subapplet.displayname = parametrisch_3d_
Applet.start
os.name = windows vista
os.arch = x86
processNativeJar: http://download.java.net/media/gluegen/webstart/gluegen-rt-natives-windows-i586.jar --> C:\Users\ochnoe\.jnlp-applet\cache\UNKNOWN\ac2bb33f38c8e89ffe12558947d6866af462a48f\gluegen-rt-natives-windows-i586.jar : 5597 bytes written
validateCertificates:
VALIDATE: gluegen-rt.dll
extractNativeLibs:
EXTRACT: gluegen-rt.dll(gluegen-rt)
processNativeJar: http://download.java.net/media/jogl/builds/archive/jsr-231-1.x-webstart-current/jogl-natives-windows-i586.jar --> C:\Users\ochnoe\.jnlp-applet\cache\UNKNOWN\ac2bb33f38c8e89ffe12558947d6866af462a48f\jogl-natives-windows-i586.jar : 61257 bytes written
validateCertificates:
VALIDATE: jogl.dll
VALIDATE: jogl_awt.dll
VALIDATE: jogl_cg.dll
extractNativeLibs:
EXTRACT: jogl.dll(jogl)
EXTRACT: jogl_awt.dll(jogl_awt)
EXTRACT: jogl_cg.dll(jogl_cg)
java.lang.ClassNotFoundException: parametrisch_3d_
    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(JNLPAppletLauncher.java:1914)
    at org.jdesktop.applet.util.JNLPAppletLauncher.access$200(JNLPAppletLauncher.java:658)
    at org.jdesktop.applet.util.JNLPAppletLauncher$5.run(JNLPAppletLauncher.java:1269)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$000(Unknown Source)
    at java.awt.EventQueue$1.run(Unknown Source)
    at java.awt.EventQueue$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessControlContext$1.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)
08.05.2011 23:39:59 org.jdesktop.applet.util.JNLPAppletLauncher displayError
SCHWERWIEGEND: Class not found: parametrisch_3d_

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