Package com.g2forge.alexandria.java.core.helpers

Class HCollection

java.lang.Object

com.g2forge.alexandria.java.core.helpers.HCollection

public final class HCollection
extends Object

Method Summary

Modifier and Type	Method	Description
static <K,C extends Collection<V>,V> void	add(Map<K,C> map, Supplier<? extends C> constructor, K key, V value)
static <T> Map<T,Integer>	asIndexMap(List<T> list)
static <T> List<T>	asList(Collection<T> collection)
static <T> List<T>	asList(T... elements)
static <T> List<T>	asListNonNull(T... elements)
static <T> List<T>	asListRepeated(int count, T element)
static <T extends Enum<T>> EnumSet<T>	asSet(Class<T> type, T... elements)
static <T> Set<T>	asSet(T... elements)
static <T> List<T>	concatenate(Collection<? extends T>... collections)
static <T> Set<T>	difference(Collection<? extends T> minuend, Collection<? extends T> subtrahend)
static <T> Collection<T>	difference(Collection<? extends T> minuend, T... subtrahend)
static <T> List<T>	emptyList()
static <T> Set<T>	emptySet()
static <T> Collection<T>	filter(Collection<? extends T> collection, Predicate<? super T> predicate)
static <T> T	get(Iterable<? extends T> collection, int index)	Get the element at the specified index within the specified collection.
static <T> T	getAny(Iterable<? extends T> iterable)
static <T> T	getFirst(Iterable<? extends T> iterable)
static <T> T	getLast(Iterable<? extends T> iterable)
static <T> int	getLast(List<? extends T> list, BiPredicate<Integer,? super T> test)
static <T> int	getLast(List<? extends T> list, Predicate<? super T> test)
static <T> T	getOne(Iterable<? extends T> iterable)	Get the single item from an iterable.
static <T> T	getOneOptional(Iterable<? extends T> iterable, ISupplier<? extends T> ifNone)
static <T> Set<T>	intersection(Collection<? extends T>... collections)
static boolean	isOne(Iterable<?> iterable, Object object)	Test if an iterable contains a single, specified, item.
static <I,O> Collection<O>	map(Function<? super I,? extends O> map, Collection<? extends I> input)
static <T> T	removeAny(Collection<T> collection)
static <T> List<T>	sort(Collection<? extends T> collection, Comparator<? super T> comparator)
static <T> Collection<T>	toCollection(Iterable<T> iterable)
static <T> List<T>	toList(Iterable<T> iterable)
static int	totalSize(Collection<?>... collections)
static <T> Set<T>	union(Collection<? extends T>... collections)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

asIndexMap

public static <T> Map<T,Integer> asIndexMap(List<T> list)

add

public static <K,C extends Collection<V>,V> void add(Map<K,C> map,
                                                                 Supplier<? extends C> constructor,
                                                                 K key,
                                                                 V value)

asSet

@SafeVarargs
public static <T extends Enum<T>> EnumSet<T> asSet(Class<T> type,
                                                   T... elements)

asList

public static <T> List<T> asList(Collection<T> collection)

asList

@SafeVarargs
public static <T> List<T> asList(T... elements)

asListRepeated

public static <T> List<T> asListRepeated(int count,
                                         T element)

asListNonNull

@SafeVarargs
public static <T> List<T> asListNonNull(T... elements)

asSet

@SafeVarargs
public static <T> Set<T> asSet(T... elements)

concatenate

@SafeVarargs
public static <T> List<T> concatenate(Collection<? extends T>... collections)

totalSize

public static int totalSize(Collection<?>... collections)

union

@SafeVarargs
public static <T> Set<T> union(Collection<? extends T>... collections)

difference

public static <T> Set<T> difference(Collection<? extends T> minuend,
                                    Collection<? extends T> subtrahend)

intersection

@SafeVarargs
public static <T> Set<T> intersection(Collection<? extends T>... collections)

difference

@SafeVarargs
public static <T> Collection<T> difference(Collection<? extends T> minuend,
                                           T... subtrahend)

filter

public static <T> Collection<T> filter(Collection<? extends T> collection,
                                       Predicate<? super T> predicate)

get

public static <T> T get(Iterable<? extends T> collection,
                        int index)

Get the element at the specified index within the specified collection. Supports negative indices to start from the end of the list.

Type Parameters:

T - A supertype of the elements of the collection.

Parameters:

collection - The collection to get an element from.

index - The index of the element to get. Must in the range -size <= index < size

Returns:

The element at the specified index.

getAny

public static <T> T getAny(Iterable<? extends T> iterable)

emptyList

public static <T> List<T> emptyList()

emptySet

public static <T> Set<T> emptySet()

getFirst

public static <T> T getFirst(Iterable<? extends T> iterable)

getLast

public static <T> T getLast(Iterable<? extends T> iterable)

getLast

public static <T> int getLast(List<? extends T> list,
                              Predicate<? super T> test)

getLast

public static <T> int getLast(List<? extends T> list,
                              BiPredicate<Integer,? super T> test)

getOne

public static <T> T getOne(Iterable<? extends T> iterable)

Get the single item from an iterable. Throw an exception if there are either fewer or more than one items.

Type Parameters:

T - The type of the items

Parameters:

iterable - The iterable to get the single item from

Returns:

The single item in the iterable

Throws:

IllegalArgumentException - if there are 0, 2 or more items in iterable

getOneOptional

public static <T> T getOneOptional(Iterable<? extends T> iterable,
                                   ISupplier<? extends T> ifNone)

isOne

public static boolean isOne(Iterable<?> iterable,
                            Object object)

Test if an iterable contains a single, specified, item.

Parameters:

iterable - The iterable to search.

object - The object to search for.

Returns:

true if iterable contains object and nothing else.

map

public static <I,O> Collection<O> map(Function<? super I,? extends O> map,
                                            Collection<? extends I> input)

removeAny

public static <T> T removeAny(Collection<T> collection)

toCollection

public static <T> Collection<T> toCollection(Iterable<T> iterable)

toList

public static <T> List<T> toList(Iterable<T> iterable)

sort

public static <T> List<T> sort(Collection<? extends T> collection,
                               Comparator<? super T> comparator)