Running single instace of the java application

Hi,
I developed a swing based application in java. I am running it through the executable jar. Each time clicking on the jar file it opens the new instance of the appliction.
But I want to open the single instance of the application i.e. If the application is running , then user tries to open another instance it should be display the error or running application only like yahoomessenger,notepad,etc.
Please tell me how it is done in java. send aly sample code or resources regarding this.
Thanks
in advance

use jni and access java PID... etc etc it is long way to do that... i think easiest way locking a file and whenever jar runs has to check file whether it is locked or not... if the file is locked, application quits.

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Any idea how the java application can get the physical memory?

Hello, everyone
Any idea how the java application can get the physical memory?
thanks in advance

I believe what yo intend to do is forbidden, but here
my answer.
when you start your application you can give your VM
the entire memory of your pc. like this this memory
is completly under your control.* headdesk *

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i would like to know whether possible to make the java .class file as .exe file to run in window environment without the help of jdk package.....if the answer is yes,,,,,is it going to use the jvm???is it come together with window os or not and start from which windows version?? or do we need to use the jre??? actually i would like to make installation package to install an application in windowsxp....i know how to do that one in vb and i've done that one before using visual studio 6.0.....is there any possible way....but please explain in easy words and way coz i might not understand if too technical...nobody can help me in my college,,,even lecturers.....thanks a lot

i would like to know whether possible to make the java .class file as >>.exe file to run in window environment without the help of jdk >>package.....Yes it is possible, there are many tools like one mentioned above to convert your java .class program to .exe and you dont need jdk for that, though you will need JVM
if the answer is yes,,,,,is it going to use the jvm???Yes it needs a JVM
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Actually I can run this command in the cygwin shell so I need to open the shell and run the command, all trough java.
so, what my process needs to do is:
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Message was edited by:
RBervini

Use "Runtime.getRuntime().exec()" to execute the SSH program,
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Hi all,
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Thanks,
itsjava

rayon.m wrote:
The solution given by ropp appears to have nothing to do with what you asked about.Ok sir, I got the point.
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~Sklave

Regarding executing the java application

Exception in thread "main" java.lang.UnsupportedClassVersionError: Hello (Unsupp
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Do you, guys, work together?
See the last answer in this thread: How database works in UCM?

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Thanks

JL.Nayak wrote:
Hi,
I have written an application in java6 and created a exe wrapper using jsmooth. Every thing is working fine. When I run my application, I gets prompted for "authorized exe". So I need to signing my exe.
My question is How can I do code signing for my application
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PavithraKarthikeyan wrote:
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Running single instace of the java application

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