This Application is intended as a launcher for ForgeGradle.
To use this in you own project, grab the latest version from github and place it in a folder in your workspace. Now just add runtime ('RELATIVE PATH TO FILE/FGLW.jar') to your dependencies in the build.gradle of the project and you are done.While ForgeGradle supports login, it is very basic and requires you to type your username and password into the command line options. While this is good (and recommended by FGLW) for the username, it is very insecure in terms of password security.
This wrapper fixes the problem by asking the user via a GUI interface. If the login is successful, a copy of the access token gets encrypted via a global key (which is stored in your .minecraft folder), and your UUID, your username and encrypted access token get saved into a file in your run folder, so even if you accidently open your file in a stream or upload it to a git repo, you access token is still safe. And even if someone gets your access token (which can be invalidated easily) and practical impossible to steal your password, as it only exists in FGLW when renewing the access token, and it is not passed to ForgeGradle. Afterwards, the access token is send to ForgeGradle, which forwards the credentials to minecraft.