Build executable jar

Are you using some IDE ?

This is how you do it in NetBeans

http://dr.berkeley.edu/REM/wiki/index.php/Making_a_Java_executable_jar_in_Netbeans

I am using Eclipse.

raed here
http://stackoverflow.com/questions/3621697/creating-an-executable-jar-file-in-eclipse

You'll find in that link above even two ways - one is in the question itself - another is inthe answer

I get this error when I try to run thecreated .jar:
Failed to load Main-Class manifest attribute

and this is even youtibe tutoarila
http://www.youtube.com/watch?v=Czmc2-hSBuk

wellcopy this .jar to .zip - unzip it and check if you have manifest.mf file and if it syas waht is your main class

If not, try to recreate it jar again

It has just this info:

Manifest-Version: 1.0

So, it didn't create correctly; try again - check these links or waht youtube video

It should be like that:

Manifest-Version: 1.0
Main-Class: JarExample

see:
http://www.astahost.com/info.php/Creating-Executable-Jar-Files_t12219.html

Do you have your project running in Eclipse as Application, - do you have configure Run configuration ?

When I open Run-> Run Configurations,
It has the right project name and right main class.

Try to recreate it - say you can do as in the video or as recommende in stackoverflow question

I did just as shown in the video!
Except for the fact that I'm using a different version of Eclipse - Galilieo.

I just did it with one of my projects and got manifest.mf like that:

Manifest-Version: 1.0
Rsrc-Class-Path: ./
Class-Path: .
Rsrc-Main-Class: Outer
Main-Class: org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader

Select allOpen in new window

I think it is OK
I have Helios, but don't think it should be different

Now, it says "Cannot find the main class" when I try to run the jar.

Did you go to Run As
select the project and the main class, then said Apply

Then you go to Export, selecte Runnable jar, then go to  Next  sleect configuration and select the file name and folder for the jar

But if you don't have specification of Main class in your manifest it would scertalinly say so

Now I do have the specification.
It says:

Manifest-Version: 1.0
Main-Class: com.HealthMonitor.Monitor

do you have such class in the appropriate folder ?

do yiou run it with

java -jar YourJarName.jar

Yes. It still says "Cannot find main class".

Does it run in Ecliopse?

Yes!

Run As -> Java Application works perfectly.

Try to do the same with some very simple project

Which java are you using on the comman line?

When I type "java -version", i get
1.6.0_20

Try to create non-executable jar from your procject and make sure it runs
when you reference you main class directly on the command line

What is the exact error message:

Does it look like this:

Could not find the main class: <something> Program will exit.

If so, what is <something> ?

I tried the steps you mentioned. Now, when I double click the .jar file, nothing happens.

I meant

java -jar YourJar.jar

Thanks a ton!

Great!