使用单线程执行程序运行任务：
import java.util.concurrent.ExecutorService;import java.util.concurrent.Executors;import java.util.concurrent.atomic.AtomicInteger;import javafx.application.Application;import javafx.beans.binding.Bindings;import javafx.beans.property.IntegerProperty;import javafx.beans.property.SimpleIntegerProperty;import javafx.concurrent.Task;import javafx.geometry.Insets;import javafx.geometry.Pos;import javafx.scene.Scene;import javafx.scene.control.Button;import javafx.scene.control.Label;import javafx.scene.control.textarea;import javafx.scene.layout.BorderPane;import javafx.scene.layout.HBox;import javafx.stage.Stage;public class QueuedTaskExample extends Application { private AtomicInteger taskCount = new AtomicInteger(0); private ExecutorService exec = Executors.newSingleThreadExecutor(r -> { Thread t = new Thread(r); t.setDaemon(true); // allows app to exit if tasks are running return t ; }); // Use the following if you want the tasks to run concurrently, instead of consecutively: // private ExecutorService exec = Executors.newCachedThreadPool(r -> { // Thread t = new Thread(r); // t.setDaemon(true); // return t ; // }); @Override public void start(Stage primaryStage) { // Just keep track of number of tasks pending/running for a status label: IntegerProperty pendingTasks = new SimpleIntegerProperty(0); Button startButton = new Button("Start"); textarea textarea = new textarea(); textarea.setEditable(true); startButton.setonAction(event -> { Task<Void> task = createTask(); // add text to text area if task's message changes: task.messageProperty().addListener((obs, oldMessage, newMessage) -> { textarea.appendText(newMessage); textarea.appendText("n"); }); // for maintaining status label: pendingTasks.set(pendingTasks.get()+1); task.setonSucceeded(taskEvent -> pendingTasks.set(pendingTasks.get()-1)); // run task in single-thread executor (will queue if another task is running): exec.submit(task); }); // layout etc HBox controls = new HBox(startButton); controls.setAlignment(Pos.CENTER); controls.setPadding(new Insets(10)); Label statusLabel = new Label(); statusLabel.textProperty().bind(Bindings.format("Pending/running tasks: %s", pendingTasks)); BorderPane root = new BorderPane(textarea, statusLabel, null, controls, null); Scene scene = new Scene(root, 600, 400); primaryStage.setScene(scene); primaryStage.show(); } @Override public void stop() { exec.shutdownNow(); } // Trivial task that counts slowly to 5, updating its message as it goes: private Task<Void> createTask() { final int taskNumber = taskCount.incrementAndGet(); return new Task<Void>() { @Override public Void call() throws Exception { for (int count=1; count<=5; count++) { Thread.sleep(1000); updateMessage("Task "+taskNumber+": Count "+count); } return null ; } }; } public static void main(String[] args) { launch(args); }}
