Как использовать non-static метод в статическом классе?

Error:(113, 11) java: non-static method play() cannot be referenced from a static context

Controller instance = new Controller();
 instance.play();

Exception in thread "JNativeHook Dispatch Thread" java.lang.IllegalStateException: Not on FX application thread; currentThread = JNativeHook Dispatch Thread
	at com.sun.javafx.tk.Toolkit.checkFxUserThread(Toolkit.java:279)
	at com.sun.javafx.tk.quantum.QuantumToolkit.checkFxUserThread(QuantumToolkit.java:423)
	at javafx.stage.Stage.<init>(Stage.java:241)
	at javafx.stage.Stage.<init>(Stage.java:227)
	at javafx.scene.control.HeavyweightDialog$1.<init>(HeavyweightDialog.java:52)
	at javafx.scene.control.HeavyweightDialog.<init>(HeavyweightDialog.java:52)
	at javafx.scene.control.Dialog.<init>(Dialog.java:263)
	at javafx.scene.control.Alert.<init>(Alert.java:245)
	at javafx.scene.control.Alert.<init>(Alert.java:223)
	at sample.Controller.<init>(Controller.java:35)
	at sample.Main$GlobalKeyListenerExample.nativeKeyPressed(Main.java:114)
	at org.jnativehook.GlobalScreen$EventDispatchTask.processKeyEvent(Unknown Source)
	at org.jnativehook.GlobalScreen$EventDispatchTask.run(Unknown Source)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
	at sample.Main$GlobalKeyListenerExample.lambda$nativeKeyReleased$0(Main.java:154)

public void nativeKeyReleased(NativeKeyEvent e) {
if (e.getKeyCode() == NativeKeyEvent.VC_F2) {
Controller.mediaPlayer.pause();
Duration ct =  Controller.mediaPlayer.getCurrentTime();
 Controller.mediaPlayer.seek(new Duration(ct.toMillis() - 1000));

Platform.runLater(() -> { Controller instance2 = new Controller();
        //154 строка:            
 instance2.startonpause.setText("123"); });
            }
        }

public class Main extends Application {

    @Override
    public void start(Stage primaryStage) throws Exception{
        Parent root = FXMLLoader.load(getClass().getResource("sample.fxml"));
        primaryStage.setTitle("Hello World");
        primaryStage.setScene(new Scene(root, 300, 275));
        primaryStage.show();

        Platform.runLater(new Runnable() {
            @Override public void run() {
                Controller instance2 = new Controller();
                instance2.aaa.setText("123");
            }
        });
    }

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

public class Controller {
    @FXML
    Label aaa;
}

Exception in thread "JavaFX Application Thread" java.lang.NullPointerException
	at sample.Main$1.run(Main.java:22)
	at com.sun.javafx.application.PlatformImpl.lambda$null$172(PlatformImpl.java:295)
	at java.security.AccessController.doPrivileged(Native Method)
	at com.sun.javafx.application.PlatformImpl.lambda$runLater$173(PlatformImpl.java:294)
	at com.sun.glass.ui.InvokeLaterDispatcher$Future.run(InvokeLaterDispatcher.java:95)
	at com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
	at com.sun.glass.ui.win.WinApplication.lambda$null$147(WinApplication.java:177)
	at java.lang.Thread.run(Thread.java:748)

<AnchorPane maxHeight="-Infinity" maxWidth="-Infinity" minHeight="-Infinity" minWidth="-Infinity" prefHeight="400.0" prefWidth="600.0" xmlns="http://javafx.com/javafx/8" xmlns:fx="http://javafx.com/fxml/1">
   <children>
      <Label fx:id="aaa" layoutX="164.0" layoutY="93.0" text="Label" />
   </children>
</AnchorPane>

но там же ясно написано, что падает из-за того, что с гуём надо работать из гуёвого треда, а не из иного.