public final void addComponent(final LwComponent component){
    if (component == null) {
      throw new IllegalArgumentException("component cannot be null");
    }
    if (myComponents.contains(component)) {
      throw new IllegalArgumentException("component is already added: " + component);
    }
    if (component.getParent() != null) {
      throw new IllegalArgumentException("component already added to another container");
    }

    // Attach to new parent
    myComponents.add(component);
    component.setParent(this);
  }
public final void addComponent(final LwComponent component)