public function __construct(array $classes)
 {
     foreach ($classes as $class) {
         require_once "trials/{$class}.php";
         $circle = new Circle($class);
         $rfl_class = new ReflectionClass($class);
         foreach ($rfl_class->getMethods() as $method) {
             if ($method->isPublic()) {
                 $circle->add_trial($this->build_trial($rfl_class, $method));
             }
         }
         $this->circles[] = $circle;
     }
 }