public void registerPresenter(RosiePresenter presenter){
  if (presenter == null) {
    throw new IllegalArgumentException("The presenter instance to be registered can't be null");
  }
  presenters.add(presenter);
}

public void registerPresenter ( RosiePresenter presenter ) { if ( presenter == null ) { throw new IllegalArgumentException ( "The presenter instance to be registered can't be null" ) ; } presenters . add ( presenter ) ; }
registers a presenter instance .
