JavaFX Running a large amount of countdown timers at once?

Question

So I can see a couple different ways to do what I need and I\'ve done a bunch of google/stack overflow searching but can\'t find really what I\'m looking for. I need to run mult

Answer 1

To add to the good answer posted by Jai, you could test different implementations for performance and find out if they use separate threads by a simple printout:

import java.io.IOException;
import javafx.animation.Animation;
import javafx.animation.KeyFrame;
import javafx.animation.PauseTransition;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.application.Platform;
import javafx.concurrent.Task;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;
import javafx.util.Duration;

public class TimersTest extends Application {

    @Override public void start(Stage stage) throws IOException {

        System.out.println("Fx thread id "+ Thread.currentThread().getId());

        VBox root = new VBox(new TimeLineCounter(), new PauseTransitionCounter(), new TaskCounter());
        stage.setScene(new Scene(root));
        stage.show();
    }

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

abstract class Counter extends Label {

    protected int count = 0;
    public Counter() {
        setAlignment(Pos.CENTER); setPrefSize(25, 25);
        count();
    }

    abstract void count();
}

class TimeLineCounter extends Counter {

    @Override
    void count() {

        Timeline timeline = new Timeline();
        timeline.setCycleCount(Animation.INDEFINITE);
        KeyFrame keyFrame = new KeyFrame(
                Duration.seconds(1),
                event -> {  setText(String.valueOf(count++) );  }
        );
        timeline.getKeyFrames().add(keyFrame);
        System.out.println("TimeLine thread id "+ Thread.currentThread().getId());
        timeline.play();
    }
}

class PauseTransitionCounter extends Counter {

    @Override
    void count() {

        PauseTransition pauseTransition = new PauseTransition(Duration.seconds(1));
        pauseTransition.setOnFinished(event ->{
            setText(String.valueOf(count++) );
            pauseTransition.play();
        });
        System.out.println("PauseTransition thread id "+ Thread.currentThread().getId());
        pauseTransition.play();
    }
}

class TaskCounter extends Counter {

    @Override
    void count() { count(this); }

    void count(final Label label) {

         Task counterTask = new Task<>() {
                @Override
                protected Void call() throws Exception {
                    try {
                        System.out.println("Task counter thread id "+ Thread.currentThread().getId());
                        while(true){
                            Platform.runLater(() -> label.setText(String.valueOf(count++)));
                            Thread.sleep(1000);
                        }
                    } catch (InterruptedException e) {e.printStackTrace();     }
                    return null;
                }
            };

            Thread th = new Thread(counterTask);   th.setDaemon(true);    th.start();
    }
}

The printout shows, as expected, that Timeline and PauseTransition are on the FX thread, while Task is not:

Fx thread id 15
TimeLine thread id 15
PauseTransition thread id 15
Task counter thread id 19