Why doesn't this implementation of Runnables (want to run it at a later stage) work at all? ( SEE The Important Part at the bottom)

mainmenu.java

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package com.skyit.consolemenu.helper;

import com.skyit.consolemenu.model.MenuItem;
import java.util.Scanner;

/**
 *
 * @author skyadmin
 */
public class MainMenuTest {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {

        // Some Threads
        MyThread thread = new MyThread();

        // Some Functions
        Runnable runner1 = () -> {
            thread.run();
        };

        Runnable runner2 = () -> {
            System.out.println("Runner2");
        };
        /**
         * Menu Part - Root First
         */
        MenuItem root = new MenuItem("Hauptmenü", null, null);
        root.setIsRoot(true);

        // Set First Level Items
        runner1.run();
        runner2.run();
        MenuItem first_a = new MenuItem("Alpha", root, runner1);
        MenuItem first_b = new MenuItem("Bravo", root, runner2);
        MenuItem first_c = new MenuItem("Charlie", root, () -> {
            System.out.println("RUN3");
        });
        root.addChild(first_a);
        root.addChild(first_b);
        root.addChild(first_c);

        // Execute Menu
        MenuItem current = root;
        Scanner s = new Scanner(System.in);
        int cursor = -1;

        while (current != null) {
            current.printMenu();
            int plus1 = (current.getChildren().size() + 1);
            if (current.isRoot()) {
                System.out.println(plus1 + ") Beenden");
            } else {
                System.out.println(plus1 + ") Voriges Menü");
            }

            System.out.print("Ihre Wahl: ");
            cursor = root.readInt(s, 1, current.getChildren().size() + 1);

            if (cursor > current.getChildren().size()) {
                current = current.getParent();
            } else {
                if (current.getRunner() != null) {
                    /** 
                     * The Important Part
                     * | | | | |
                     * V V V V V
                     **/
                    current.run();
                }
                current = current.getChildAt(cursor - 1);
            }

        }

    }

}