Java SE (Java Platform, Standard Edition)

Is it possible to package an application or a library in a .jar file that contains .jar files in it, so that those .jar files are accessible as part of the classpath? If so, does it require special code to retrieve the .jar files from within the .jar file they are distributed in? Or is it as simple as creating a URL to the .jar file inside a .jar file so that classloaders are able to look inside of it? I do not want to unjar the .jar files inside of the main .jar file to the disk. I want to keep them contained inside of it, but be able to use them at runtime.

Thanks.