java - Why is main method used in JavaFX Application when start() already exist

Question

The starting point for a JavaFX application is start method. But in the sample JavaFX applications, there is a main method included as well. What is the use of main method in this particular case and why was there a need to define start() as starting point for JavaFX. Couldn't we simply use the main method to define a starting point like Swings?

A sample HelloWorld application:

public class HelloWorld extends Application {

    @Override
    public void start(Stage primaryStage) {
        Button btn = new Button("Hello World");
        btn.setOnAction(new EventHandler<ActionEvent>() {
            @Override
            public void handle(ActionEvent event) {
                System.out.println("Hello World!");
            }
        });

        StackPane root = new StackPane();
        root.getChildren().add(btn);

        Scene scene = new Scene(root, 300, 250);

        primaryStage.setTitle("Hello World!");
        primaryStage.setScene(scene);
        primaryStage.show();
    }

    public static void main(String[] args) {
        launch(args);
    }
}

Answer 1

From Oracle Docs ,

The main() method is not required for JavaFX applications when the JAR file for the application is created with the JavaFX Packager tool, which embeds the JavaFX Launcher in the JAR file. However, it is useful to include the main() method so you can run JAR files that were created without the JavaFX Launcher, such as when using an IDE in which the JavaFX tools are not fully integrated. Also, Swing applications that embed JavaFX code require the main() method.