(Display a running fan) Write a program that displays a running fan, as shown in Figure 15.33c

/*********************************************************************************
* (Display a running fan) Write a program that displays a running fan, as shown  *
* in Figure 15.33c. Use the Pause, Resume, Reverse buttons to pause, resume,     *
* and reverse fan running.                                                       *
*********************************************************************************/
import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.control.Button;
import javafx.geometry.Pos;
import javafx.stage.Stage;

public class Exercise_15_28 extends Application {
	@Override // Override the start method in the Application class
	public void start(Stage primaryStage) {
		FanPane fanPane = new FanPane();

		// Create three buttons
		Button btPause = new Button("Pause");
		Button btResume = new Button("Resume");
		Button btReverse = new Button("Reverse");
		HBox hBox = new HBox(5);
		hBox.setAlignment(Pos.CENTER);

		// Place nodes in panes
		hBox.getChildren().addAll(btPause, btResume, btReverse);


		// Create a border pane
		BorderPane borderPane = new BorderPane();
		borderPane.setCenter(fanPane);
		borderPane.setBottom(hBox);

		btPause.setOnAction(e -> {
			fanPane.pause();
		});

		btResume.setOnAction(e -> {
			fanPane.play();
		});

		btReverse.setOnAction(e -> {
			fanPane.reverse();
		});

		// Create a scene and place it in the stage
		Scene scene = new Scene(borderPane, 250, 250);
		primaryStage.setTitle("Exercise_15_28"); // Set the stage title
		primaryStage.setScene(scene); // Place the scene in the stage
		primaryStage.show(); // Display the stage

		fanPane.requestFocus();
	}
}

FanPane.java

import javafx.collections.ObservableList;
import javafx.scene.layout.StackPane;
import javafx.scene.layout.Pane;
import javafx.scene.shape.Circle;
import javafx.scene.shape.Arc;
import javafx.scene.shape.ArcType;
import javafx.scene.paint.Color;
import javafx.scene.Node;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.animation.Timeline;
import javafx.animation.KeyFrame;
import javafx.util.Duration;

public  class FanPane extends StackPane {
	private double startAngle = 15; // Start angle of arcs
	private Timeline fan; // animation
	private Pane blades = getBlades(); // Create four arcs
	private ObservableList<Node> list = blades.getChildren(); // List of arcs

	/**  Construct a FanPane */
	public FanPane() {
		getChildren().addAll(getCircle(), blades);
		fan = new Timeline(
			new KeyFrame(Duration.millis(50), e -> spinFan()));
		fan.setCycleCount(Timeline.INDEFINITE);
		fan.play(); // Start animation
	}

	/** Animate fan blades */
	protected void spinFan() {
		for (int i = 0; i < list.size(); i++) {
			Arc a = (Arc)list.get(i);
			a.setStartAngle(a.getStartAngle() + startAngle);
		}
	}

	/** Pause animation */
	public void pause() {
		fan.pause();
	}

	/** Resume animation */
	public void play() {
		fan.play();
	}

	/** Reverse the direction of fan spin */
	protected void reverse() {
		startAngle *= -1;
	}

	/** Add four arcs to a pane and place them in a stack pane */
	private Pane getBlades() {
		Pane pane = new Pane();
		double angle = 0;
		for (int i = 0; i < 4; i++) {
			Arc arc = new Arc(125, 115, 90, 90, angle + 90, 50);
			arc.setFill(Color.BLACK);
			arc.setType(ArcType.ROUND);
			pane.getChildren().add(arc);
			angle += 90;
		}
		return pane;
	}

	/** Return a Circle */
	private Circle getCircle() {
		Circle c = new Circle();
		c.setRadius(100);
		c.setStroke(Color.BLACK);
		c.setFill(Color.WHITE);
		return c;
	}
}