JsJava.java

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import static com.google.common.io.Resources.getResource;
import static com.teamdev.jxbrowser.engine.RenderingMode.HARDWARE_ACCELERATED;
import static javax.swing.SwingUtilities.invokeLater;

import com.teamdev.jxbrowser.browser.Browser;
import com.teamdev.jxbrowser.browser.callback.InjectJsCallback;
import com.teamdev.jxbrowser.engine.Engine;
import com.teamdev.jxbrowser.js.JsAccessible;
import com.teamdev.jxbrowser.js.JsObject;
import com.teamdev.jxbrowser.view.swing.BrowserView;
import java.awt.BorderLayout;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.net.URL;
import javax.swing.JFrame;
import javax.swing.WindowConstants;

/**
 * This example demonstrates how to invoke Java from JavaScript.
 */
public class JsJava {

    /**
     * A Java object to inject into JavaScript.
     *
     * <p>Note: Only public classes and static nested classes can be injected into JS.
     */
    @JsAccessible
    public static final class JavaObject {

        @SuppressWarnings("unused") // To be called from JavaScript.
        public String sayHelloTo(String name) {
            return "Hello " + name + "! This message comes from Java.";
        }
    }

    public static void main(String[] args) {
        Engine engine = Engine.newInstance(HARDWARE_ACCELERATED);
        Browser browser = engine.newBrowser();

        // Inject an instance of the Java object into JavaScript
        // before JavaScript is executed on the loaded web page:
        browser.set(InjectJsCallback.class, params -> {
            JsObject window = params.frame().executeJavaScript("window");
            if (window != null) {
                window.putProperty("java", new JavaObject());
            }
            return InjectJsCallback.Response.proceed();
        });

        invokeLater(() -> {
            showGui(browser);

            // Load a page that calls a Java method.
            URL resource = getResource(JsJava.class, "/index.html");
            browser.navigation().loadUrl(resource.getPath());
        });
    }

    private static void showGui(Browser browser) {
        BrowserView view = BrowserView.newInstance(browser);

        JFrame frame = new JFrame("Calling Java from JavaScript");
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                browser.engine().close();
            }
        });
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        frame.add(view, BorderLayout.CENTER);
        frame.setSize(800, 600);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}