Package com.google.common.collect

Class ForwardingSortedMultiset<E>

  • All Implemented Interfaces:
    Multiset<E>, SortedMultiset<E>, java.lang.Iterable<E>, java.util.Collection<E>
    @Beta
@GwtCompatible(emulated=true)
public abstract class ForwardingSortedMultiset<E>
extends ForwardingMultiset<E>
implements SortedMultiset<E>
    A sorted multiset which forwards all its method calls to another sorted multiset. Subclasses should override one or more methods to modify the behavior of the backing multiset as desired per the decorator pattern.

    Warning: The methods of ForwardingSortedMultiset forward indiscriminately to the methods of the delegate. For example, overriding ForwardingMultiset.add(Object, int) alone will not change the behavior of ForwardingCollection.add(Object), which can lead to unexpected behavior. In this case, you should override add(Object) as well, either providing your own implementation, or delegating to the provided standardAdd method.

    The standard methods and any collection views they return are not guaranteed to be thread-safe, even when all of the methods that they depend on are thread-safe.

    Since:
    15.0

    • Constructor Detail

      • ForwardingSortedMultiset

        protected ForwardingSortedMultiset()
        Constructor for use by subclasses.

    • Method Detail

      • delegate

        protected abstract SortedMultiset<E> delegate()
        Description copied from class: ForwardingObject
        Returns the backing delegate instance that methods are forwarded to. Abstract subclasses generally override this method with an abstract method that has a more specific return type, such as ForwardingSet.delegate(). Concrete subclasses override this method to supply the instance being decorated.
        Specified by:
        delegate in class ForwardingMultiset<E>

      • elementSet

        public java.util.NavigableSet<E> elementSet()
        Description copied from interface: Multiset
        Returns the set of distinct elements contained in this multiset. The element set is backed by the same data as the multiset, so any change to either is immediately reflected in the other. The order of the elements in the element set is unspecified.

        If the element set supports any removal operations, these necessarily cause all occurrences of the removed element(s) to be removed from the multiset. Implementations are not expected to support the add operations, although this is possible.

        A common use for the element set is to find the number of distinct elements in the multiset: elementSet().size().

        Specified by:
        elementSet in interface Multiset<E>
        Specified by:
        elementSet in interface SortedMultiset<E>
        Overrides:
        elementSet in class ForwardingMultiset<E>
        Returns:
        a view of the set of distinct elements in this multiset

      • comparator

        public java.util.Comparator<? super E> comparator()
        Description copied from interface: SortedMultiset
        Returns the comparator that orders this multiset, or Ordering.natural() if the natural ordering of the elements is used.
        Specified by:
        comparator in interface SortedMultiset<E>

      • pollFirstEntry

        public Multiset.Entry<E> pollFirstEntry()
        Description copied from interface: SortedMultiset
        Returns and removes the entry associated with the lowest element in this multiset, or returns null if this multiset is empty.
        Specified by:
        pollFirstEntry in interface SortedMultiset<E>

      • pollLastEntry

        public Multiset.Entry<E> pollLastEntry()
        Description copied from interface: SortedMultiset
        Returns and removes the entry associated with the greatest element in this multiset, or returns null if this multiset is empty.
        Specified by:
        pollLastEntry in interface SortedMultiset<E>

      • headMultiset

        public SortedMultiset<E> headMultiset​(E upperBound,
                                      BoundType boundType)
        Description copied from interface: SortedMultiset
        Returns a view of this multiset restricted to the elements less than upperBound, optionally including upperBound itself. The returned multiset is a view of this multiset, so changes to one will be reflected in the other. The returned multiset supports all operations that this multiset supports.

        The returned multiset will throw an IllegalArgumentException on attempts to add elements outside its range.

        Specified by:
        headMultiset in interface SortedMultiset<E>

      • subMultiset

        public SortedMultiset<E> subMultiset​(E lowerBound,
                                     BoundType lowerBoundType,
                                     E upperBound,
                                     BoundType upperBoundType)
        Description copied from interface: SortedMultiset
        Returns a view of this multiset restricted to the range between lowerBound and upperBound. The returned multiset is a view of this multiset, so changes to one will be reflected in the other. The returned multiset supports all operations that this multiset supports.

        The returned multiset will throw an IllegalArgumentException on attempts to add elements outside its range.

        This method is equivalent to tailMultiset(lowerBound, lowerBoundType).headMultiset(upperBound, upperBoundType).

        Specified by:
        subMultiset in interface SortedMultiset<E>

      • tailMultiset

        public SortedMultiset<E> tailMultiset​(E lowerBound,
                                      BoundType boundType)
        Description copied from interface: SortedMultiset
        Returns a view of this multiset restricted to the elements greater than lowerBound, optionally including lowerBound itself. The returned multiset is a view of this multiset, so changes to one will be reflected in the other. The returned multiset supports all operations that this multiset supports.

        The returned multiset will throw an IllegalArgumentException on attempts to add elements outside its range.

        Specified by:
        tailMultiset in interface SortedMultiset<E>