Jar files get whatever Shell icon that was installed as part of the .jar file association. If you changed this it would change for every jar on the system.
So the only ways to get an "application icon" that I am aware of are (1.) create a shortcut that runs the jar and has a custom icon, (2.) create a separate launcher EXE in another language, or (3.) create an EXE wrapper around the jar file that can have a custom icon.
The latter can have issues, since some of the wrappers out there have to extract the jar to a temporary folder on every run. A few other claim to use another technique, e.g.
Launch4j.
I'm not sure what you mean by "application name." Are you talking about one of the extended properties such as Product Name, Description, etc?
Some of these can be handled via a shortcut, all of them using a custom launcher, and perhaps some of them using a wrapper if its build tool makes provisions for it. But since a jar file is just a renamed zip file I don't think its format makes any provision for most of those EXE-specific extended properties, most of which occur in an embedded resource within the EXE.