question: public boolean canHandle ( AppEvent event , boolean bubbleDown ) { if ( supportedEvents != null && supportedEvents . contains ( event . getType ( ) ) ) return true ; if ( children != null && bubbleDown ) { for ( Controller c : children ) { if ( c . canHandle ( event , bubbleDown ) ) return true ; } } return false ; }
target:  Determines if the controller can handle the particular event. Default implementation checks against registered event types then queries all child controllers if bubbleUp set to true.