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Java applet stopped working in Java 7.21

Posted on 2013-06-10
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Last Modified: 2013-06-14
Hi,

We have a Java applet client in our application. Since we updated our machines to Java 7.21, it stopped working. This is what I got on console.

Java Plug-in 10.21.2.11
Using JRE version 1.7.0_21-b11 Java HotSpot(TM) Client VM
User home directory = C:\Users\Cityuser
----------------------------------------------------
c:   clear console window
f:   finalize objects on finalization queue
g:   garbage collect
h:   display this help message
l:   dump classloader list
m:   print memory usage
o:   trigger logging
q:   hide console
r:   reload policy configuration
s:   dump system and deployment properties
t:   dump thread list
v:   dump thread stack
x:   clear classloader cache
0-5: set trace level to <n>
----------------------------------------------------



It just hangs after this. Its Windows 7 64 bit with 32 bit Java. Its not working on any browser(chrome,IE,firefox etc)

It think it is not working because of some security related changes in Java.

Moreover, Applet was running intermittently means it did work on some versions of Java 7 and stopped on others versions since we moved to Java 7. Strange part is that applet is running fine on one developer machine. We compare settings of this machine with rest of all machines, everything is same.

Now our customer wants use Java 7.21 ASAP. Anybody could please help us to resolve it.

Cheers
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Question by:IPA_tech
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15 Comments
 
LVL 86

Expert Comment

by:CEHJ
ID: 39234567
Its Windows 7 64 bit with 32 bit Java.
Try using 64 bit plugin after uninstalling that one:
http://java.com/en/download/faq/java_win64bit.xml
0
 

Author Comment

by:IPA_tech
ID: 39234877
Hi CEHJ,

Thanks for the reply. We tried and even its not working on Windows XP 32 bit. Everything is 32 bit.

Is there any change in Java security manager which stops the applet from running?

Cheers
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LVL 27

Expert Comment

by:rrz
ID: 39234927
0
Netscaler Common Configuration How To guides

If you use NetScaler you will want to see these guides. The NetScaler How To Guides show administrators how to get NetScaler up and configured by providing instructions for common scenarios and some not so common ones.

 
LVL 86

Expert Comment

by:CEHJ
ID: 39234976
Starting with Java SE 7 Update 21 in April 2013, all Java Applets and Web Start Applications should be signed with a trusted certificate.
For the best possible user experience, your Applets and Web Start Applications should be signed.
Java SE 7u21 will introduce changes to Java browser plug-in behavior, encouraging application authors and vendors to sign code with a certificate from a trusted Certificate Authority.
So - is it mandatory to sign or not!?
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Author Comment

by:IPA_tech
ID: 39235015
I am signing the jar using "C:\Program Files\Java\jdk1.6.0\bin\JARSIGNER.exe" etc. Is there a different way for 7.21?

Java browser plug-in behavior?
Do I need to install any new plugin
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LVL 86

Accepted Solution

by:
CEHJ earned 500 total points
ID: 39235122
jarsigner is the signing executable. ALL jars of the applet need to be signed
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Author Comment

by:IPA_tech
ID: 39235142
Yes we are signing our own jars only. I think You mean even the third party also...right?

If yes then how can I sign the third party jars which are quite old? I dont have the code or anything?
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LVL 86

Expert Comment

by:CEHJ
ID: 39235173
If yes then how can I sign the third party jars which are quite old? I dont have the code or anything?
You don't need the code
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Author Comment

by:IPA_tech
ID: 39235207
Let me try it tomorrow then and will post my feedback. thanks
0
 
LVL 27

Expert Comment

by:rrz
ID: 39235876
CEHJ>So - is it mandatory to sign or not!?
I don't know. All I can post is my experience on my desktop. I used to be able to run my old  applets, from a local HTML file, without signing them. Now (with version  1.7.0_21-b11), they throw
java.lang.SecurityException: Your security settings have blocked a local application from
running
I tried to change the Security Level (see Security tab in Java Control Panel) but it seems that High is the only acceptable level. If I do lower the level in the control panel, then it automatically reverts back to the High level. I am able to self-sign my applets and run them (after clicking the annoying prompts).

IPA_tech,
It is strange that you don't get any messages in your Java Console.
You could go into your Java Control Panel and on the Advanced tab under debugging check Enable tracing and click Apply. Try running again afterwards.
What happens when you go to
http://www.java.com/en/download/testjava.jsp.
http://docs.oracle.com/javase/tutorial/deployment/applet/getStarted.html 
Do the applets run ? Do any prompts come up? Do you see any messages in the Java console when tracing is enabled?
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LVL 86

Expert Comment

by:CEHJ
ID: 39236046
Yes. Sounds like a massive (and panicked) kludge
0
 

Author Comment

by:IPA_tech
ID: 39236989
rrz@871311  ---> Tracking is already enabled and I can't see anything except what I mentioned above. Even testjava.jsp says everything is fine.

I will sign all jars and then try today. Will back once I complete it.
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LVL 27

Expert Comment

by:rrz
ID: 39238237
>Tracking is already enabled and I can't see anything except what I mentioned
I am surprised by that. When I go to Sun's testjava.jsp my Java Console prints a couple hundred lines. They include security, network, and basic applet lifecycle messages.
Did you check your log directory? It should be in your user home directory. If you don't know where your log directory is located, then focus on your Java Console and type  s  on your keyboard. Look for the deployment property
deployment.user.logdir
0
 

Author Closing Comment

by:IPA_tech
ID: 39247009
This solution was one part of the issue and helped me to fix the issue. I have made few changes like changed the location from etc folder to user folder, merging my jars and etc.
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LVL 86

Expert Comment

by:CEHJ
ID: 39247609
Err ... rrz@871311 made a larger contribution to that than i. Why no points split?
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