ModuleTestController.php

<?php

namespace Drupal\module_test\Controller;

use Drupal\module_autoload_test\SomeClass;

/**
 * Controller routines for module_test routes.
 */
class ModuleTestController {
    
    /**
     * Returns dynamically invoked hook results for the 'module_test' module.
     *
     * @return array
     *   Renderable array.
     */
    public function hookDynamicLoadingInvoke() {
        $result = \Drupal::moduleHandler()->invoke('module_test', 'test_hook');
        return $result['module_test'];
    }
    
    /**
     * Returns dynamically invoked hook results for all modules.
     *
     * @return array
     *   Renderable array.
     */
    public function hookDynamicLoadingInvokeAll() {
        $result = \Drupal::moduleHandler()->invokeAll('test_hook');
        return $result['module_test'];
    }
    
    /**
     * Returns the result of an autoloaded class's public method.
     *
     * @return array
     *   Renderable array.
     */
    public function testClassLoading() {
        $markup = NULL;
        if (class_exists('Drupal\\module_autoload_test\\SomeClass')) {
            $obj = new SomeClass();
            $markup = $obj->testMethod();
        }
        return [
            '#markup' => $markup,
        ];
    }

}