code: @SuppressWarnings( "unchecked" )
      public <ValueType> Collection<ValueType> getPropertyAsCollection( Property propertyId,
                                                                        Class<ValueType> type ) {
          if (nodeProperties == null) return null;
          return (Collection<ValueType>)nodeProperties.get(propertyId);
      }
docs: Get the node's value for this supplied property, casting the result to a {@link Collection} of the supplied type.
  
  @param <ValueType> the type of the value expected
  @param propertyId the property identifier
  @param type the class denoting the type of value expected; may not be null
  @return the value, or null if there is no property on this node