How to use PropertyResourceBundle

I am learning Java internationalization, but I haven't been able find out how to use PropertyResourceBundle. The documentation says that:
"ResourceBundle.getBundle automatically looks for the appropriate properties file and creates a PropertyResourceBundle that refers to it"
I imagine the search is in the class path, But what names should I give to the properties files?

Thanks,

Alejandro Barrero

The Javadoc for ResourceBundle.getBundle goes into detail on this

Thanks Tim. I just dind't read in detail.

Well, I am still having problems. I created two properties files:

com/caveman/internationalization/Paperless_en.properties
com/caveman/internationalization/Paperlessen.properties

I can get then with a class's classloader getResourceAsStream, but I am getting the error:

Can't find bundle for base name Paperless, locale en
The documentation says "Otherwise, getBundle attempts to locate a property resource file. It generates a path name from the candidate bundle name by replacing all "." characters with "/" and appending the string ".properties"."

I am at a loss.

It finally worked with
resourceBunble = ResourceBundle.getBundle("com.caveman.internationalization.Paperless", locale, classLoader);