code: public <C extends Collection<T>> Map<Boolean, C> partitioningTo(Predicate<? super T> predicate,
              Supplier<C> collectionFactory) {
          return collect(Collectors.partitioningBy(predicate, Collectors.toCollection(collectionFactory)));
      }
docs: Returns a {@code Map<Boolean, C>} which contains two partitions of the
  input elements according to a {@code Predicate}.
  
  <p>
  This is a <a href="package-summary.html#StreamOps">terminal</a>
  operation.
  
  <p>
  There are no guarantees on the type, mutability, serializability, or
  thread-safety of the {@code Map} returned.
  
  @param <C> the type of {@code Collection} used as returned {@code Map}
  values.
  @param predicate a predicate used for classifying input elements
  @param collectionFactory a function which returns a new empty
  {@code Collection} which will be used to store the stream
  elements.
  @return a {@code Map<Boolean, C>} which {@link Boolean#TRUE} key is
  mapped to the collection of the stream elements for which
  predicate is true and {@link Boolean#FALSE} key is mapped to the
  collection of all other stream elements.
  
  @see #partitioningBy(Predicate, Collector)
  @see Collectors#partitioningBy(Predicate)
  @since 0.2.2