org.d2ab.collection

Interface SizedIterable<T>

All Superinterfaces:

java.lang.Iterable<T>

All Known Subinterfaces:

BiSequence<L,R>, CharSeq, DoubleSequence, EntrySequence<K,V>, IntSequence, IterableCollection<T>, LongSequence, Sequence<T>

All Known Implementing Classes:

BiMappedCollection, BiMappedList.RandomAccessList, BiMappedList.SequentialList, ChainedCollection, ChainedList, ChainingIterable, CollectionSequence, EquivalentSizeSequence, FilteredCollection, FilteredList, IterableList, ListSequence, MappedCollection, MappedList.RandomAccessList, MappedList.SequentialList, ReverseList, SizedIterable.FixedSizedIterable

public interface SizedIterable<T>
extends java.lang.Iterable<T>

An Iterable which can also report the size of its contents.

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	SizedIterable.FixedSizedIterable<T>
static class	SizedIterable.SizeType

Method Summary

Modifier and Type	Method and Description
static <T> SizedIterable<T>	from(java.util.Collection<T> collection)
static <T> SizedIterable<T>	from(java.util.Collection<T> collection, SizedIterable.SizeType sizeType)
static <T> SizedIterable<T>	from(java.lang.Iterable<T> iterable)
default boolean	isEmpty()
static boolean	isEmpty(SizedIterable<?> iterable)
default int	size()
static int	size(SizedIterable<?> iterable)
default int	sizeIfKnown()
default SizedIterable.SizeType	sizeType() The type of size this SizedIterable has, which provides the guarantees that can be assumed on the evaluation of the size() and isEmpty() methods.

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Method Detail

from

static <T> SizedIterable<T> from(java.lang.Iterable<T> iterable)

from

static <T> SizedIterable<T> from(java.util.Collection<T> collection)

from

static <T> SizedIterable<T> from(java.util.Collection<T> collection,
                                 SizedIterable.SizeType sizeType)

size

static int size(SizedIterable<?> iterable)

isEmpty

static boolean isEmpty(SizedIterable<?> iterable)

sizeType

default SizedIterable.SizeType sizeType()

The type of size this SizedIterable has, which provides the guarantees that can be assumed on the evaluation of the size() and isEmpty() methods.

If this method returns SizedIterable.SizeType.AVAILABLE, size() and isEmpty() is guaranteed to evaluate correct results without having to traverse the SizedIterable.

If this method returns SizedIterable.SizeType.FIXED, size() and isEmpty() is guaranteed to evaluate to the same result for the lifetime of the SizedIterable without having to traverse it.

If this method returns SizedIterable.SizeType.UNAVAILABLE, size() and isEmpty() may require traversal of the SizedIterable to determine their results, and may thus be an O(n) operation.

If this method returns SizedIterable.SizeType.INFINITE, size() should always throw UnsupportedOperationException and isEmpty() should always return false.

size

default int size()

sizeIfKnown

default int sizeIfKnown()

Returns:

the size of this SizedIterable if known a-priori, or -1 if the size is not known.

isEmpty

default boolean isEmpty()