LoginKit
· LoginKit provides a complete and secure identity solution to let your community use their Snapchat account as a quick way to sign up and log in.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window loginkit-2.1.1.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.