import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;

import javafx.application.Application;
import javafx.concurrent.Worker.State;
import javafx.scene.Scene;
import javafx.scene.layout.AnchorPane;
import javafx.scene.web.WebEngine;
import javafx.scene.web.WebView;
import javafx.stage.Stage;
import netscape.javascript.JSObject;

public class WebViewJsCallbackTest extends Application {

    private static final DateFormat DATE_FORMAT = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");

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

    public class JavaScriptBridge {
        public void callback(String data) {
            System.out.println("callback retrieved: " + data);
        }
    }

    @Override
    public void start(Stage primaryStage) throws Exception {
        WebView webView = new WebView();
        primaryStage.setScene(new Scene(new AnchorPane(webView)));
        primaryStage.show();

        final WebEngine webEngine = webView.getEngine();
		webEngine.setJavaScriptEnabled(true); 
        webEngine.load(getClass().getClassLoader().getResource("page.html").toExternalForm());

        webEngine.getLoadWorker().stateProperty().addListener((observableValue, oldValue, newValue) -> {
            if (newValue == State.SUCCEEDED) {
                JSObject window = (JSObject) webEngine.executeScript("window");
                window.setMember("javaApp", new JavaScriptBridge());
            }
        });

        webEngine.setOnAlert(event -> {
            System.out.println(DATE_FORMAT.format(new Date()) + " alerted: " + event.getData());
        });
    }

}