net.emaze.dysfunctional

Class Reductions

java.lang.Object

net.emaze.dysfunctional.Reductions

public abstract class Reductions
extends Object

reduce, any, every, count, maximum, minimum.

Author:

rferranti

Constructor Summary

Constructors

Constructor and Description
Reductions()

Method Summary

Methods

Modifier and Type	Method and Description
static <E> boolean	any(E[] array, Predicate<E> predicate) Yields true if ANY predicate application on the given array yields true (giving up on the first positive match).
static <E> boolean	any(Iterable<E> iterable, Predicate<E> predicate) Yields true if ANY predicate application on the given iterable yields true (giving up on the first positive match).
static <E> boolean	any(Iterator<E> iterator, Predicate<E> predicate) Yields true if ANY predicate application on the given iterator yields true (giving up on the first positive match).
static <E> long	count(Iterable<E> iterable) Counts elements contained in the iterable.
static <E> long	count(Iterator<E> iterator) Counts elements contained in the iterator.
static <E> int	counti(Iterable<E> iterable) Counts elements contained in the iterable.
static <E> int	counti(Iterator<E> iterator) Counts elements contained in the iterator.
static <E> boolean	every(E[] array, Predicate<E> predicate) Yields true if EVERY predicate application on the given array yields true.
static <E> boolean	every(Iterable<E> iterable, Predicate<E> predicate) Yields true if EVERY predicate application on the given iterable yields true.
static <E> boolean	every(Iterator<E> iterator, Predicate<E> predicate) Yields true if EVERY predicate application on the given iterator yields true.
static <E,C extends Comparator<E>> E	maximum(Iterator<E> iterator, C comparator, E init) Returns the max element contained in the iterator
static <E extends Comparable<E>> E	maximum(Iterator<E> iterator, E init) Returns the max element contained in the iterator
static <E,C extends Comparator<E>> E	minimum(Iterator<E> iterator, C comparator, E init) Returns the min element contained in the iterator
static <E extends Comparable<E>> E	minimum(Iterator<E> iterator, E init) Returns the min element contained in the iterator
static <R,E> R	reduce(E[] array, BinaryDelegate<R,R,E> delegate, R init) Reduces an array of elements using the passed delegate.
static <R,E> R	reduce(Iterable<E> iterable, BinaryDelegate<R,R,E> delegate, R init) Reduces an iterator of elements using the passed delegate.
static <R,E> R	reduce(Iterator<E> iterator, BinaryDelegate<R,R,E> delegate, R init) Reduces an iterator of elements using the passed delegate.

Methods inherited from class java.lang.Object

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

Constructor Detail

Reductions

public Reductions()

Method Detail

reduce

public static <R,E> R reduce(Iterator<E> iterator,
             BinaryDelegate<R,R,E> delegate,
             R init)

Reduces an iterator of elements using the passed delegate.

Type Parameters:

R - the result type parameter

E - the element type parameter

Parameters:

iterator - the iterator to be consumed

delegate - the reduction delegate

init - the initial value for reductions

Returns:

the reduced value

reduce

public static <R,E> R reduce(Iterable<E> iterable,
             BinaryDelegate<R,R,E> delegate,
             R init)

Reduces an iterator of elements using the passed delegate.

Type Parameters:

R - the result type parameter

E - the element type parameter

Parameters:

iterable - the iterable to be consumed

delegate - the reduction delegate

init - the initial value for reductions

Returns:

the reduced value

reduce

public static <R,E> R reduce(E[] array,
             BinaryDelegate<R,R,E> delegate,
             R init)

Reduces an array of elements using the passed delegate.

Type Parameters:

R - the result type parameter

E - the element type parameter

Parameters:

array - the array to be consumed

delegate - the reduction delegate

init - the initial value for reductions

Returns:

the reduced value

any

public static <E> boolean any(Iterable<E> iterable,
              Predicate<E> predicate)

Yields true if ANY predicate application on the given iterable yields true (giving up on the first positive match).

Type Parameters:

E - the iterable element type parameter

Parameters:

iterable - the iterable where elements are fetched from

predicate - the predicate applied to every element until a match is found

Returns:

true if ANY predicate application yields true (gives up on the first positive match)

any

public static <E> boolean any(Iterator<E> iterator,
              Predicate<E> predicate)

Yields true if ANY predicate application on the given iterator yields true (giving up on the first positive match).

Type Parameters:

E - the iterator element type parameter

Parameters:

iterator - the iterator where elements are fetched from

predicate - the predicate applied to every element until a match is found

Returns:

true if ANY predicate application yields true (gives up on the first positive match)

any

public static <E> boolean any(E[] array,
              Predicate<E> predicate)

Yields true if ANY predicate application on the given array yields true (giving up on the first positive match).

Type Parameters:

E - the array element type parameter

Parameters:

array - the array where elements are fetched from

predicate - the predicate applied to every element until a match is found

Returns:

true if ANY predicate application yields true (gives up on the first positive match)

every

public static <E> boolean every(Iterable<E> iterable,
                Predicate<E> predicate)

Yields true if EVERY predicate application on the given iterable yields true.

Type Parameters:

E - the iterable element type parameter

Parameters:

iterable - the iterable where elements are fetched from

predicate - the predicate applied to every element fetched from the iterable

Returns:

true if EVERY predicate application yields true

every

public static <E> boolean every(Iterator<E> iterator,
                Predicate<E> predicate)

Yields true if EVERY predicate application on the given iterator yields true.

Type Parameters:

E - the iterator element type parameter

Parameters:

iterator - the iterator where elements are fetched from

predicate - the predicate applied to every element fetched from the iterator

Returns:

true if EVERY predicate application yields true

every

public static <E> boolean every(E[] array,
                Predicate<E> predicate)

Yields true if EVERY predicate application on the given array yields true.

Type Parameters:

E - the array element type parameter

Parameters:

array - the array where elements are fetched from

predicate - the predicate applied to every element fetched from the array

Returns:

true if EVERY predicate application yields true

count

public static <E> long count(Iterator<E> iterator)

Counts elements contained in the iterator.

Type Parameters:

E - the iterator element type parameter

Parameters:

iterator - the iterator to be consumed

Returns:

the size of the iterator

count

public static <E> long count(Iterable<E> iterable)

Counts elements contained in the iterable.

Type Parameters:

E - the iterable element type parameter

Parameters:

iterable - the iterable to be consumed

Returns:

the size of the iterable

counti

public static <E> int counti(Iterator<E> iterator)

Counts elements contained in the iterator.

Type Parameters:

E - the iterator element type parameter

Parameters:

iterator - the iterator to be consumed

Returns:

the size of the iterator

counti

public static <E> int counti(Iterable<E> iterable)

Counts elements contained in the iterable.

Type Parameters:

E - the iterable element type parameter

Parameters:

iterable - the iterable to be consumed

Returns:

the size of the iterator

maximum

public static <E,C extends Comparator<E>> E maximum(Iterator<E> iterator,
                                    C comparator,
                                    E init)

Returns the max element contained in the iterator

Type Parameters:

E - the iterator element type parameter

C - the comparator type parameter

Parameters:

iterator - the iterator to be consumed

comparator - the comparator to be used to evaluate the max element

init - the initial value to be used

Returns:

the max element contained in the iterator

maximum

public static <E extends Comparable<E>> E maximum(Iterator<E> iterator,
                                  E init)

Returns the max element contained in the iterator

Type Parameters:

E - the iterator element type parameter

Parameters:

iterator - the iterator to be consumed

init - the initial value to be used

Returns:

the max element contained in the iterator

minimum

public static <E,C extends Comparator<E>> E minimum(Iterator<E> iterator,
                                    C comparator,
                                    E init)

Returns the min element contained in the iterator

Type Parameters:

E - the iterator element type parameter

C - the comparator type parameter

Parameters:

iterator - the iterator to be consumed

comparator - the comparator to be used to evaluate the min element

init - the initial value to be used

Returns:

the min element contained in the iterator

minimum

public static <E extends Comparable<E>> E minimum(Iterator<E> iterator,
                                  E init)

Returns the min element contained in the iterator

Type Parameters:

E - the iterator element type parameter

Parameters:

iterator - the iterator to be consumed

init - the initial value to be used

Returns:

the min element contained in the iterator