// else, put a new pluggable in corresponding outlet
if (plugged.containsKey(where) &&
plugged.get(where).id().equals(what.id())) {
plugged.get(where).refresh(); // just refresh, nothing else
} else {
final IsOutlet outlet = outlet(where);
if (!outlet.isVisible()) Log.warn("Outlet at place " + where + " is not visible, but you are plugging " + what + " there");
outlet.clear();
outlet.add(what.asWidget());
what.asWidget().addStyleName(generatePlugCSSClassName(what));
plugged.put(where, what);
Log.debug("Plugged " + what.id() + " into outlet at place " + where);
what.setPlace(where);
what.refresh();