org.magicwerk.brownies.collections

Interface ICollectionTools

public interface ICollectionTools

ICollectionTools offers default implementations of Collection functionality.

See Also:

Collection

Method Summary

Modifier and Type	Method and Description
static <E> boolean	containsIf(java.util.Collection<E> coll, java.util.function.Predicate<? super E> predicate) Determines whether the list contains a matching element.
static <E> int	countIf(java.util.Collection<E> coll, java.util.function.Predicate<? super E> predicate) Counts how many elements in the list match the predicate.
static <E,C extends java.util.Collection<E>> C	filter(java.util.Collection<E> coll, java.util.function.Predicate<? super E> predicate, java.util.function.Supplier<C> factory) Create a new list by applying the specified filter to all elements.
static <E,R,C extends java.util.Collection<R>> IList<R>	filterMap(java.util.Collection<E> coll, java.util.function.Predicate<E> filter, java.util.function.Function<E,R> func) Create a new list by applying the specified filter first and then the mapping function to all elements selected.
static <E,R,C extends java.util.Collection<R>> C	filterMap(java.util.Collection<E> coll, java.util.function.Predicate<E> filter, java.util.function.Function<E,R> func, java.util.function.Supplier<C> factory) Create a new collection by applying the specified filter first and then the mapping function to all elements selected.
static <E,R,RC extends java.util.Collection<R>,C extends java.util.Collection<R>> C	flatMap(java.util.Collection<E> coll, java.util.function.Function<E,RC> func, java.util.function.Supplier<C> factory) Create a new list by applying the specified mapping function to all elements.
static <E> E	getFirst(java.util.Collection<E> coll) Returns the first element stored in the collection.
static <E> E	getFirstOrNull(java.util.Collection<E> coll) Returns the first element stored in the collection.
static <E> E	getIf(java.util.Collection<E> coll, java.util.function.Predicate<? super E> predicate) Returns the first element stored in the collection which matches the predicate.
static <E> E	getSingle(java.util.Collection<E> coll) Returns the only element stored in the collection.
static <E> E	getSingleOrNull(java.util.Collection<E> coll) Returns the only element stored in the collection or null if the collection is empty.
static <E,R,C extends java.util.Collection<R>> C	map(java.util.Collection<E> coll, java.util.function.Function<E,R> func, java.util.function.Supplier<C> factory) Create a new list by applying the specified mapping function to all elements.
static <E,R> IList<R>	mapFilter(java.util.Collection<E> coll, java.util.function.Function<E,R> func, java.util.function.Predicate<R> filter) Create a new list by applying the specified mapping function to all elements and then filtering it.
static <E,R,C extends java.util.Collection<R>> C	mapFilter(java.util.Collection<E> coll, java.util.function.Function<E,R> func, java.util.function.Predicate<R> filter, java.util.function.Supplier<C> factory) Create a new collection by applying the specified mapping function to all elements and then filtering it.

Method Detail

getFirst

static <E> E getFirst(java.util.Collection<E> coll)

Returns the first element stored in the collection. If the collection is empty, a NoSuchElementException is thrown.

Returns:

first element stored in the collection

getFirstOrNull

static <E> E getFirstOrNull(java.util.Collection<E> coll)

Returns the first element stored in the collection. If the collection is empty, null is returned.

Returns:

first element stored in the collection or null if empty

getSingle

static <E> E getSingle(java.util.Collection<E> coll)

Returns the only element stored in the collection. If the collection size is not 1, a NoSuchElementException is thrown.

Returns:

only element stored in the collection

getSingleOrNull

static <E> E getSingleOrNull(java.util.Collection<E> coll)

Returns the only element stored in the collection or null if the collection is empty. If the collection's size is greater than 1, a NoSuchElementException is thrown.

Returns:

only element stored in the collection or null if empty

getIf

static <E> E getIf(java.util.Collection<E> coll,
                   java.util.function.Predicate<? super E> predicate)

Returns the first element stored in the collection which matches the predicate. If the collection is empty of no element matches, null is returned.

Returns:

first element matching the predicate or null if not founds

containsIf

static <E> boolean containsIf(java.util.Collection<E> coll,
                              java.util.function.Predicate<? super E> predicate)

Determines whether the list contains a matching element.

Parameters:

predicate - predicate used to search element

Returns:

true if the list contains a matching element, false otherwise

countIf

static <E> int countIf(java.util.Collection<E> coll,
                       java.util.function.Predicate<? super E> predicate)

Counts how many elements in the list match the predicate.

Parameters:

predicate - a predicate which returns true for elements to be counted

Returns:

count how many elements in the list match the predicate

filter

static <E,C extends java.util.Collection<E>> C filter(java.util.Collection<E> coll,
                                                      java.util.function.Predicate<? super E> predicate,
                                                      java.util.function.Supplier<C> factory)

Create a new list by applying the specified filter to all elements.

Parameters:

predicate - filter predicate

Returns:

created list

map

static <E,R,C extends java.util.Collection<R>> C map(java.util.Collection<E> coll,
                                                     java.util.function.Function<E,R> func,
                                                     java.util.function.Supplier<C> factory)

Create a new list by applying the specified mapping function to all elements.

Parameters:

func - mapping function

Returns:

created list

flatMap

static <E,R,RC extends java.util.Collection<R>,C extends java.util.Collection<R>> C flatMap(java.util.Collection<E> coll,
                                                                                            java.util.function.Function<E,RC> func,
                                                                                            java.util.function.Supplier<C> factory)

Create a new list by applying the specified mapping function to all elements.

Parameters:

func - mapping function

Returns:

created list

mapFilter

static <E,R> IList<R> mapFilter(java.util.Collection<E> coll,
                                java.util.function.Function<E,R> func,
                                java.util.function.Predicate<R> filter)

Create a new list by applying the specified mapping function to all elements and then filtering it.

Parameters:

func - mapping function

filter - filter predicate

Returns:

created list

mapFilter

static <E,R,C extends java.util.Collection<R>> C mapFilter(java.util.Collection<E> coll,
                                                           java.util.function.Function<E,R> func,
                                                           java.util.function.Predicate<R> filter,
                                                           java.util.function.Supplier<C> factory)

Create a new collection by applying the specified mapping function to all elements and then filtering it.

Parameters:

func - mapping function

filter - filter predicate

factory - factory to create collection

Returns:

created list

filterMap

static <E,R,C extends java.util.Collection<R>> IList<R> filterMap(java.util.Collection<E> coll,
                                                                  java.util.function.Predicate<E> filter,
                                                                  java.util.function.Function<E,R> func)

Create a new list by applying the specified filter first and then the mapping function to all elements selected.

Parameters:

filter - filter predicate

func - mapping function

Returns:

created list

filterMap

static <E,R,C extends java.util.Collection<R>> C filterMap(java.util.Collection<E> coll,
                                                           java.util.function.Predicate<E> filter,
                                                           java.util.function.Function<E,R> func,
                                                           java.util.function.Supplier<C> factory)

Create a new collection by applying the specified filter first and then the mapping function to all elements selected.

Parameters:

filter - filter predicate

func - mapping function

factory - factory to create collection

Returns:

created list