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Detecting if the client browser disabled/allows java applets ?

P: n/a
On one of my web pages there is an java applets which works fine on my computer.
However I noticed on some other computer that the run of java applets are disabled.
I got an error message "Classnotfound"
Is there a way to detect (with cgi resp. javascript) if java applets are allowed?
I would like to show a simple picture instead of the applet pane if applets are not allowed.

Wladimir

Jul 23 '05 #1
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12 Replies


P: n/a
On Mon, 1 Nov 2004 20:30:55 +0100, Wladimir Borsov wrote:

This is not a Java question.
On one of my web pages
URL?
..there is an java applets which works fine on my computer.
However I noticed on some other computer that the run of java applets are disabled.
I got an error message "Classnotfound"
There is no such thing. I will make some guesses.
These machines are..
a) Running Win
b) Using IE as a browser
c) the browsers are throwing 'ClassNotFoundException's
<http://www.physci.org/codes/javafaq.jsp#exact>
<http://www.physci.org/codes/javafaq.jsp#appletie>
d) this reports '1.1.4'
<http://www.physci.org/pc/property.jsp?prop=java.version>
Is there a way to detect (with cgi resp. javascript) if java applets are allowed?
You can detect if Java is enabled using JAvascript,
but that is not the problem here.
I would like to show a simple picture instead of the applet pane if applets are not allowed.


Yes, to both the problem you thought you had, as well as the
problem I suspect you actually have. You need to fix both to
get the untlimate effect you want. Both can be done without
Javascript.

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
Jul 23 '05 #2

P: n/a
On Tue, 02 Nov 2004 05:01:07 GMT, Andrew Thompson wrote:
This is not a Java question.


Oops! Try, "This is not a *Javascript* question".

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
Jul 23 '05 #3

P: n/a
Wladimir Borsov wrote:
Is there a way to detect (with cgi resp. javascript) if java applets are allowed?
I would like to show a simple picture instead of the applet pane if applets are not allowed.


<applet ...>
<param ...>
<param ...>
<param ...>
<p>The message here will only be shown when Java is disabled or not
supported.</p>
</applet>

--
Toby A Inkster BSc (Hons) ARCS
Contact Me ~ http://tobyinkster.co.uk/contact

Jul 23 '05 #4

P: n/a
On Tue, 02 Nov 2004 07:42:27 +0000, Toby Inkster wrote:
<applet ...> .... <p>The message here will only be shown when Java is disabled or not
supported.</p>
</applet>


Wrong! The 'no applet' part of the applet element as specified
above *only* covers the situation where Java is not and never
has been installed. If Java is installed, but *disabled*, that
message will not show.

To cover that, you need to specify an 'alt' attribute, which
displays for browsers with Java installed, but disabled.

As an aside, the OP mis-diagnosed the actual problem.
The browser's concerned would not be getting any message that
included 'Classnotfound' (sic) if this was a problem with
the alt/alternate HTML parts of the applet element.
The JVM is obviously being invoked, to produce that message.

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
Jul 23 '05 #5

P: n/a

"Wladimir Borsov" <wl*******@gmx.net> wrote in message
news:cm*************@news.t-online.com...
On one of my web pages there is an java applets which works fine on my computer. However I noticed on some other computer that the run of java applets are disabled. I got an error message "Classnotfound"
Is there a way to detect (with cgi resp. javascript) if java applets are allowed? I would like to show a simple picture instead of the applet pane if

applets are not allowed.

You don't really need to detect it. Anything inside of the APPLET or OBJECT
tags that you use to embed the applet (other than PARAM tags) is rendered on
browsers that aren't running Java.

<applet ...>
<param ...>
<param ...>
<p><img src="..." alt="..." ...></p>
</applet>

Jul 23 '05 #6

P: n/a
Wladimir Borsov wrote:
On one of my web pages there is an java applets which works fine on
my computer.
However I noticed on some other computer that the run of java applets
are disabled.
I got an error message "Classnotfound"
Is there a way to detect (with cgi resp. javascript) if java applets
are allowed?
I would like to show a simple picture instead of the applet pane if
applets are not allowed.


You put whatever you want between <applet> and </applet> which is then
displayed by browsers that do not support Java (or have Java deactivated).
However the "Classnotfound" error seems to be something different: What Java
version does your applet use? And what Java version do you have installed on
your computer?

Boris
Jul 23 '05 #7

P: n/a
<applet ...alt="">
<param ...>
<param ...><img src="file.gif">
</applet>

The Classnotfound error message is a different issue.

--
George Hester
__________________________________
"Wladimir Borsov" <wl*******@gmx.net> wrote in message news:cm*************@news.t-online.com...
On one of my web pages there is an java applets which works fine on my computer.
However I noticed on some other computer that the run of java applets are disabled.
I got an error message "Classnotfound"
Is there a way to detect (with cgi resp. javascript) if java applets are allowed?
I would like to show a simple picture instead of the applet pane if applets are not allowed.

Wladimir

Jul 23 '05 #8

P: n/a
On Wed, 03 Nov 2004 12:48:48 GMT, George Hester wrote:
<applet ...alt="">


That provides the message "" to anybody using an UA
with Java *disabled* (think library, corporate networks,
'school' and the internet cafe*), that's a wide audience
to which to present a message of ""...

* That is simply listing the people who may not have access
to Java *even if they wanted to*, let alone the home users
who *choose* not to install the Java plug-in.

But one more time. THIS IS NOTHING TO DO WITH JS.
(apologies for shouting)

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
Jul 23 '05 #9

P: n/a
"Andrew Thompson" <Se********@www.invalid> wrote in message news:jp****************************@40tude.net...
On Wed, 03 Nov 2004 12:48:48 GMT, George Hester wrote:
<applet ...alt="">


That provides the message "" to anybody using an UA
with Java *disabled* (think library, corporate networks,
'school' and the internet cafe*), that's a wide audience
to which to present a message of ""...

* That is simply listing the people who may not have access
to Java *even if they wanted to*, let alone the home users
who *choose* not to install the Java plug-in.

But one more time. THIS IS NOTHING TO DO WITH JS.
(apologies for shouting)

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane


Hi Andrew. Actually I have never seen it work too well. The user wanted an image and what I provided did do
that. I try to answer the questions as they are posed. So yes alt="Hi" is supposed to present "something" to the
user when the browser is Java challenged I just never seen it work too well. The image replacement does. He
could also just insert text there as well instead of the image.

George Hester
__________________________________
Jul 23 '05 #10

P: n/a
On Thu, 04 Nov 2004 00:50:44 GMT, George Hester wrote:
So yes alt="Hi" is supposed to present "something" to the
user when the browser is Java challenged I just never seen it work too well.


I OTOH, have witnessed it working perfectly.

All indications from your posts are that you have
a) never used a browser other than IE, and..
b) do not have the first clue about how to get applets into
a web-page for a wide variety of users.

Please stop confusing the OP.

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
Jul 23 '05 #11

P: n/a
"Andrew Thompson" <Se********@www.invalid> wrote in message news:1g******************************@40tude.net.. .
On Thu, 04 Nov 2004 00:50:44 GMT, George Hester wrote:
So yes alt="Hi" is supposed to present "something" to the
user when the browser is Java challenged I just never seen it work too well.


I OTOH, have witnessed it working perfectly.

All indications from your posts are that you have
a) never used a browser other than IE, and..
b) do not have the first clue about how to get applets into
a web-page for a wide variety of users.

Please stop confusing the OP.

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane


Andrew I am going to take your nasty remarks as par for the course of this newsgroup. You belong here.

Thanks.

George Hester
__________________________________
Jul 23 '05 #12

P: n/a
On Thu, 04 Nov 2004 05:02:17 GMT, George Hester wrote:
Andrew I am going to take your nasty remarks as par for the course of this newsgroup.
If it slows the rate at which you deliver bogus
information about Java, that is a good thing.
..You belong here.
Thanks!
Thanks.


You're welcome, ..anytime. ;-)

--
Andrew Thompson
http://www.PhySci.org/codes/ Web & IT Help
http://www.PhySci.org/ Open-source software suite
http://www.1point1C.org/ Science & Technology
http://www.LensEscapes.com/ Images that escape the mundane
Jul 23 '05 #13

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