Apache Commons Collections 4.4 · org.apache.commons.collections4.IterableUtils

Modifier and Type	Class and Description
private static class	IterableUtils.UnmodifiableIterable<E> Inner class to distinguish unmodifiable instances.

Modifier and Type	Field and Description
pack-priv static final FluentIterable<E>	EMPTY_ITERABLE An empty iterable.

Access	Constructor and Description
public	IterableUtils()

Method Summary

Modifier and Type	Method and Description
public static < the element type E> Iterable<E>	Returns: a bounded view on the specified iterable boundedIterable(final Iterable<E> the iterable to limit, may not be null iterable, final long the maximum number of elements, must not be negative maxSize) Returns a view of the given iterable that contains at most the given number of elements.
public static < the element type E> Iterable<E>	Returns: a new iterable, combining the provided iterables chainedIterable(final Iterable<? extends E> the first iterable, may not be null a, final Iterable<? extends E> the second iterable, may not be null b) Combines two iterables into a single iterable.
public static < the element type E> Iterable<E>	Returns: a new iterable, combining the provided iterables chainedIterable(final Iterable<? extends E> the first iterable, may not be null a, final Iterable<? extends E> the second iterable, may not be null b, final Iterable<? extends E> the third iterable, may not be null c) Combines three iterables into a single iterable.
public static < the element type E> Iterable<E>	Returns: a new iterable, combining the provided iterables chainedIterable(final Iterable<? extends E> the first iterable, may not be null a, final Iterable<? extends E> the second iterable, may not be null b, final Iterable<? extends E> the third iterable, may not be null c, final Iterable<? extends E> the fourth iterable, may not be null d) Combines four iterables into a single iterable.
public static < the element type E> Iterable<E>	Returns: a new iterable, combining the provided iterables chainedIterable(final Iterable<? extends E>... the iterables to combine, may not be null iterables) Combines the provided iterables into a single iterable.
pack-priv static void	checkNotNull(final Iterable<?> the iterable to check iterable) Fail-fast check for null arguments.
pack-priv static void	checkNotNull(final Iterable<?>... the iterables to check iterables) Fail-fast check for null arguments.
public static < the element type E> Iterable<E>	Returns: a filtered view on the specified iterable collatedIterable(final Iterable<? extends E> the first iterable, may not be null a, final Iterable<? extends E> the second iterable, may not be null b) Combines the two provided iterables into an ordered iterable using natural ordering.
public static < the element type E> Iterable<E>	Returns: a filtered view on the specified iterable collatedIterable(final Comparator<? super E> the comparator defining an ordering over the elements, may be null, in which case natural ordering will be used comparator, final Iterable<? extends E> the first iterable, may not be null a, final Iterable<? extends E> the second iterable, may not be null b) Combines the two provided iterables into an ordered iterable using the provided comparator.
public static < the type of object the `Iterable` contains E> boolean	Returns: true if the object is contained in the iterable, false otherwise contains(final Iterable<E> the iterable to check, may be null iterable, final Object the object to check object) Checks if the object is contained in the given iterable.
public static < the type of object the `Iterable` contains E> boolean	Returns: true if the object is contained in the iterable, false otherwise contains(final Iterable<? extends E> the iterable to check, may be null iterable, final E the object to check object, final Equator<? super E> the equator to use to check, may not be null equator) Checks if the object is contained in the given iterable.
public static < the type of object the `Iterable` contains E> long	Returns: the number of matches for the predicate in the collection countMatches(final Iterable<E> the `Iterable` to get the input from, may be null input, final Predicate<? super E> the predicate to use, may not be null predicate) Counts the number of elements in the input iterable that match the predicate.
public static < the element type E> Iterable<E>	Returns: an empty iterable if the argument is null emptyIfNull(final Iterable<E> the iterable, may be null iterable) Returns an immutable empty iterable if the argument is null, or the argument itself otherwise.
public static < the element type E> Iterable<E>	Returns: an empty iterable emptyIterable() Gets an empty iterable.
private static < the element type E> Iterator<E>	Returns: an empty iterator if the argument is `null` emptyIteratorIfNull(final Iterable<E> the iterable, possibly `null` iterable) Returns an empty iterator if the argument is `null`, or `iterable.iterator()` otherwise.
public static < the element type E> Iterable<E>	Returns: a filtered view on the specified iterable filteredIterable(final Iterable<E> the iterable to filter, may not be null iterable, final Predicate<? super E> the predicate used to filter elements, may not be null predicate) Returns a view of the given iterable that only contains elements matching the provided predicate.
public static < the element type E> E	Returns: the first element of the iterable which matches the predicate or null if none could be found find(final Iterable<E> the iterable to search, may be null iterable, final Predicate<? super E> the predicate to use, may not be null predicate) Finds the first element in the given iterable which matches the given predicate.
public static < the type of object in the `Iterable`. T> T	Returns: the first object first(final Iterable<T> the `Iterable` to get a value from, may be null iterable) Shortcut for `get(iterator, 0)`.
public static < the element type E> void	forEach(final Iterable<E> the iterator to use, may be null iterable, final Closure<? super E> the closure to apply to each element, may not be null closure) Applies the closure to each element of the provided iterable.
public static < the type of object the `Iterable` contains E> E	Returns: the last element in the iterable, or null if iterable is null or empty forEachButLast(final Iterable<E> the iterable to get the input from, may be null iterable, final Closure<? super E> the closure to perform, may not be null closure) Executes the given closure on each but the last element in the iterable.
public static < the element type that the `Iterable` may contain E, the element type of the object to find T extends E> int	Returns: the number of occurrences of obj in iterable frequency(final Iterable<E> the `Iterable` to search iterable, final T the object to find the cardinality of obj) Returns the number of occurrences of the provided object in the iterable.
public static < the type of object in the `Iterable`. T> T	Returns: the object at the specified index get(final Iterable<T> the `Iterable` to get a value from, may be null iterable, final int the index to get index) Returns the `index`-th value in the `iterable`'s `Iterator`, throwing `IndexOutOfBoundsException` if there is no such element.
public static < the element type E> int	Returns: the index of the first element which matches the predicate or -1 if none matches indexOf(final Iterable<E> the iterable to search, may be null iterable, final Predicate<? super E> the predicate to use, may not be null predicate) Returns the index of the first element in the specified iterable that matches the given predicate.
public static boolean	Returns: true if the iterable is null or empty, false otherwise isEmpty(final Iterable<?> the `to use`, may be null iterable) Answers true if the provided iterable is empty.
public static < the element type E> Iterable<E>	Returns: a view of the iterable, providing an infinite loop over its elements loopingIterable(final Iterable<E> the iterable to loop, may not be null iterable) Returns a view of the given iterable which will cycle infinitely over its elements.
public static < the type of object the `Iterable` contains E> boolean	Returns: true if every element of the collection matches the predicate or if the collection is empty, false otherwise matchesAll(final Iterable<E> the `Iterable` to use, may be null iterable, final Predicate<? super E> the predicate to use, may not be null predicate) Answers true if a predicate is true for every element of an iterable.
public static < the type of object the `Iterable` contains E> boolean	Returns: true if any element of the collection matches the predicate, false otherwise matchesAny(final Iterable<E> the `Iterable` to use, may be null iterable, final Predicate<? super E> the predicate to use, may not be null predicate) Answers true if a predicate is true for any element of the iterable.
public static < the type of object the `Iterable` contains O> List<List<O>>	Returns: a list containing the output collections partition(final Iterable<? extends O> the iterable to partition, may be null iterable, final Predicate<? super O> the predicate to use, may not be null predicate) Partitions all elements from iterable into separate output collections, based on the evaluation of the given predicate.
public static < the type of object the `Iterable` contains O> List<List<O>>	Returns: a list containing the output collections partition(final Iterable<? extends O> the collection to get the input from, may be null iterable, final Predicate<? super O>... the predicates to use, may not be null predicates) Partitions all elements from iterable into separate output collections, based on the evaluation of the given predicates.
public static < the type of object the `Iterable` contains O, the type of the output `Collection` R extends Collection<O>> List<R>	Returns: a list containing the output collections partition(final Iterable<? extends O> the collection to get the input from, may be null iterable, final Factory<R> the factory used to create the output collections partitionFactory, final Predicate<? super O>... the predicates to use, may not be null predicates) Partitions all elements from iterable into separate output collections, based on the evaluation of the given predicates.
public static < the element type E> Iterable<E>	Returns: a reversed view of the specified iterable reversedIterable(final Iterable<E> the iterable to use, may not be null iterable) Returns a reversed view of the given iterable.
public static int	Returns: the number of elements contained in the iterable size(final Iterable<?> the iterable to check, may be null iterable) Returns the number of elements contained in the given iterator.
public static < the element type E> Iterable<E>	Returns: a view of the specified iterable, skipping the first N elements skippingIterable(final Iterable<E> the iterable to use, may not be null iterable, final long the number of elements to skip from the start, must not be negative elementsToSkip) Returns a view of the given iterable that skips the first N elements.
public static < the element type E> List<E>	Returns: a list of the iterator contents toList(final Iterable<E> the iterable to use, may be null iterable) Gets a new list with the contents of the provided iterable.
public static < the element type E> String	Returns: a string representation of `iterable` toString(final Iterable<E> the iterable to convert to a string, may be null iterable) Returns a string representation of the elements of the specified iterable.
public static < the element type E> String	Returns: a string representation of `iterable` toString(final Iterable<E> the iterable to convert to a string, may be null iterable, final Transformer<? super E, String> the transformer used to get a string representation of an element transformer) Returns a string representation of the elements of the specified iterable.
public static < the element type E> String	Returns: a string representation of `iterable` toString(final Iterable<E> the iterable to convert to a string, may be null iterable, final Transformer<? super E, String> the transformer used to get a string representation of an element transformer, final String the string to delimit elements delimiter, final String the prefix, prepended to the string representation prefix, final String the suffix, appended to the string representation suffix) Returns a string representation of the elements of the specified iterable.
public static < the input element type I, the output element type O> Iterable<O>	Returns: a transformed view of the specified iterable transformedIterable(final Iterable<I> the iterable to transform, may not be null iterable, final Transformer<? super I, ? extends O> the transformer, must not be null transformer) Returns a transformed view of the given iterable where all of its elements have been transformed by the provided transformer.
public static < the element type E> Iterable<E>	Returns: a unique view of the specified iterable uniqueIterable(final Iterable<E> the iterable to use, may not be null iterable) Returns a unique view of the given iterable.
public static < the element type E> Iterable<E>	Returns: an unmodifiable view of the specified iterable unmodifiableIterable(final Iterable<E> the iterable to use, may not be null iterable) Returns an unmodifiable view of the given iterable.
public static < the element type E> Iterable<E>	Returns: a new iterable, interleaving the provided iterables zippingIterable(final Iterable<? extends E> the first iterable, may not be null a, final Iterable<? extends E> the second iterable, may not be null b) Interleaves two iterables into a single iterable.
public static < the element type E> Iterable<E>	Returns: a new iterable, interleaving the provided iterables zippingIterable(final Iterable<? extends E> the first iterable, may not be null first, final Iterable<? extends E>... the array of iterables to interleave, may not be null others) Interleaves two iterables into a single iterable.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll toString wait wait wait

public Class IterableUtils

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