Application and JavaFX subsystems

The very first API, javafx.application.Application, represents the program itself. It prepares everything for us to start using JavaFX and is an entry point for all standalone JavaFX applications. It does the following:

• Initializes JavaFX toolkit (subsystems and native libraries required to run JavaFX)
• Starts JavaFX Application Thread (a thread where all UI work happens) and all working threads
• Constructs the Application instance (which provides a starting point for your program) and calls the user-overridden methods
• Handles application command line parameters
• Handles all cleanup and shutdown once the application ends

Let's look closely at each of these steps.