Design Java Swing-based UIs with Apple’s Interface Builder

nib4j is a simple but powerfull Java library that permits the use of Apple’s
Interface Builder to design Swing-based user interfaces. It creates Swing
menus, frames and dialogs from Carbon nib files and provides a complete
separation of UI and application code.

The new version supports the creation of cross-platform UIs with use of
JGoodies Forms. With the nib4j Viewer you can try out your Swing interfaces
without writing any code and do a cross-platform test showing different Look
& Feels.

nib4j is completely free for non-commercial use. A developer license is US$
169.

More informations at:
http://www.nib4j.com