public Set < K > getUnavailableNodes ( ) { final Set < K > result = new HashSet < K > ( ) ; for ( final Map . Entry < K , ManagedItem < Boolean > > entry : _map . entrySet ( ) ) { if ( ! entry . getValue ( ) . _value . booleanValue ( ) && ! isExpired ( entry . getValue ( ) ) ) { result . add ( entry . getKey ( ) ) ; } } return result ; }
A set of nodes that are stored as unavailable .