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define the main class in a jar

chen young
Ranch Hand

Joined: Sep 09, 2005
Posts: 197

I created a swing application.
I want to create a jar (I know how to do that) that will activate the application meaning, if the user will push on X.jar the application will start running.

How can I define the main class?

Ulf Dittmer

Joined: Mar 22, 2005
Posts: 42958
Like with all applications, you need a class with a main method to start the application. Then you need to add a manifest file to the jar which references the class with the main method; see JarFiles for more details.
Rob Spoor

Joined: Oct 27, 2005
Posts: 20137

You have to create a manifest file and include the following line:

Then, when creating the JAR file, specify that you want to include a manifest file, and use the one you just created/

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chen young
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Joined: Sep 09, 2005
Posts: 197

I add all the necessaries directories (also properties and .classpath) to the jar.
When I am trying to run the jar I get the fallowing error:

Exception in thread "main" java.util.MissingResourceException: Can't find bundle for base name rcyProperties, locale en_US
at java.util.ResourceBundle.throwMissingResourceException(Unknown Source)
at java.util.ResourceBundle.getBundleImpl(Unknown Source)
at java.util.ResourceBundle.getBundle(Unknown Source)
at utils.RcyUtils.getResourceBundle(
at utils.RcyUtils.getImageIcon(
at gui.BootScreen.<init>(
at main.StartRcy.main(

The properties directory is define in the .classpath file.
Should I need to add this directory also into the manifest.txt (and how)?

I agree. Here's the link:
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