JavaFX Concurrency Examples

A simple JavaFX tutorial through simple snippets.

Example 1: Concurrency

Here are the code:

Step 1: Create Project

1. Open your favorite Java IDE.
2. In the menu go to File --> Create New Project.

Step 2: Dependencies

No dependencies are needed for this project.

Step 3: Write Code

Our code will comprise the following java files:

• ConcurrencyExample.java

1. In your editor or IDE, create a file known as ConcurrencyExample.java.
2. Then add the following code:

(a). ConcurrencyExample.java

First, go ahead and add the following imports:

import javafx.application.Application;
import javafx.application.Platform;
import javafx.scene.Scene;
import javafx.scene.control.ProgressBar;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

We will need to extend our class using the extend keyword. By doing that our class can make use of inheritance to derive properties and functions defined in the parent class.

public class ConcurrencyExample extends Application {

Our class will have the following methods:

• void main(String[] args)
• void start(Stage primaryStage)
• void run()
• void run()

Every Java Program must have a main method. This is the entry point of all Java applications include JavaFX. Add a main() method and inside it invoke the launch() function.

    public static void main(String[] args) {

We have 3methods to override in this class. Here are those methods:

• public void start(Stage primaryStage) {
• public void run() {
• public void run() {
  Prepend the @Override modifier to your method. Then add implementation code as follows:

    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("JavaFX App");

        ProgressBar progressBar = new ProgressBar(0);

        VBox vBox = new VBox(progressBar);
        Scene scene = new Scene(vBox, 960, 600);

        primaryStage.setScene(scene);
        primaryStage.show();

        Thread taskThread = new Thread(new Runnable() {
            @Override
            public void run() {
                double progress = 0;
                for(int i=0; i<10; i++){
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }

Prepend the code>@Override</code modifier to your method. Then add implementation code as follows:

                        @Override
                        public void run() {
                            progressBar.setProgress(reportedProgress);
                        }

Here is the full code:

package com.jenkov.javafx.concurrency;

import javafx.application.Application;
import javafx.application.Platform;
import javafx.scene.Scene;
import javafx.scene.control.ProgressBar;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class ConcurrencyExample extends Application {
    public static void main(String[] args) {
        launch(args);
    }

    @Override
    public void start(Stage primaryStage) {
        primaryStage.setTitle("JavaFX App");

        ProgressBar progressBar = new ProgressBar(0);

        VBox vBox = new VBox(progressBar);
        Scene scene = new Scene(vBox, 960, 600);

        primaryStage.setScene(scene);
        primaryStage.show();

        Thread taskThread = new Thread(new Runnable() {
            @Override
            public void run() {
                double progress = 0;
                for(int i=0; i<10; i++){
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                    progress += 0.1;

                    double reportedProgress = progress;
                    Platform.runLater(new Runnable() {
                        @Override
                        public void run() {
                            progressBar.setProgress(reportedProgress);
                        }
                    });
                }

            }
        });

        taskThread.start();
    }

}

Download

Download the code using the below links: