no.finntech.lambdacompanion

Class Pair<L,R>

java.lang.Object

no.finntech.lambdacompanion.Pair<L,R>

Type Parameters:

L - type of the left side

R - type of the right side

public final class Pair<L,R>
extends Object

Represents two values of two possible types together (a union of 2.)

Constructor Summary

Constructors

Constructor and Description
Pair(L left, R right)

Method Summary

Modifier and Type	Method and Description
boolean	equals(Object o)
L	getLeft()
R	getRight()
int	hashCode()
static <L,R> Pair<List<L>,List<R>>	of(List<Either<L,R>> collection) Given a list of Either[L,R] that can be a mixed collection of Left and Right, groups left side values into one list and right side values into another list and return both lists together as a Pair (makes a union of the values contained within a collection of disjoint unions)
static <K,U> Collector<Pair<K,U>,?,Map<K,U>>	toMap() Shorthand to collect a Stream of Pair-s to a Map using left value as the key and right value as the value of the Map entries
Map.Entry<L,R>	toMapEntry()

Methods inherited from class java.lang.Object

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

Constructor Detail

Pair

public Pair(L left,
            R right)

Method Detail

getLeft

public L getLeft()

getRight

public R getRight()

toMapEntry

public Map.Entry<L,R> toMapEntry()

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

of

public static <L,R> Pair<List<L>,List<R>> of(List<Either<L,R>> collection)

Given a list of Either[L,R] that can be a mixed collection of Left and Right, groups left side values into one list and right side values into another list and return both lists together as a Pair (makes a union of the values contained within a collection of disjoint unions)

Type Parameters:

L - type of the left side

R - type of the right side

Parameters:

collection - a collection of disjoint unions

Returns:

a Pair of the left values and right values

toMap

public static <K,U> Collector<Pair<K,U>,?,Map<K,U>> toMap()

Shorthand to collect a Stream of Pair-s to a Map using left value as the key and right value as the value of the Map entries

Warning: this Collector will only work when the Stream does not contain duplicate left values in the Pair-s it contains.

Type Parameters:

K - k

U - u

Returns:

a Collector