JavaFX对话框在关闭后显示为阻塞，未正确解除

import javafx.application.Application;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.Dialog;
import javafx.scene.control.Label;
import javafx.scene.layout.VBox;
import javafx.stage.Stage;

public class DialogExample extends Application {

    @Override
    public void start(Stage primaryStage) {
        Button showDialogButton = new Button("Show Dialog");
        showDialogButton.setOnAction(event -> {
            Dialog<String> dialog = new Dialog<>();
            dialog.setTitle("Example Dialog");
            dialog.setHeaderText("This is an example dialog.");

            Label contentLabel = new Label("Dialog content");
            dialog.getDialogPane().setContent(new VBox(contentLabel));

            Button closeButton = new Button("Close");
            closeButton.setOnAction(closeEvent -> {
                dialog.close(); // 关闭对话框
            });
            dialog.getDialogPane().getButtonTypes().add(ButtonType.CLOSE);

            dialog.showAndWait(); // 显示对话框并阻塞当前线程
        });

        VBox root = new VBox(showDialogButton);
        Scene scene = new Scene(root, 300, 200);
        primaryStage.setScene(scene);
        primaryStage.show();
    }

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