WipeFreeSpaceGUI2 version 1.0 has just been released.
It is an almost-complete rewrite of the original GUI, keeping some of the logic, but this time not using any frameworks, just pure Java. More portable, and can be developed further (unlike the previous version).
The UI has been re-arranged and new, hand-made icons (Inkscape again) have been introduced, just to mention the visual changes. Many, many refactorings, simplifications, fixes and other improvements have been made "under the hood", both in the code and in the build system.
The new GUI has all the functionalities of the previous version + support for WipeFreeSpace options that have been introduced since the last old GUI version was released.
WipeFreeSpaceGUI2 still does require WipeFreeSpace to do the actual wiping.
Get the new GUI at https://sourceforge.net/projects/wipefreespace/files/WipeFreeSpaceGUI2/1.0/ and enjoy!