io.atlassian.fugue

Class Pair<A,B>

java.lang.Object

io.atlassian.fugue.Pair<A,B>

All Implemented Interfaces:

Serializable

public final class Pair<A,B>
extends Object
implements Serializable

Represents a pair of objects.

Since:

1.0

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Pair(A left, B right) Constructor for Pair.

Method Summary

Modifier and Type	Method and Description
static <A,B> Pair<B,B>	ap(Pair<A,A> aa, Pair<Function<A,B>,Function<A,B>> ff) Performs function application within an homogeneous pair (applicative functor pattern).
boolean	equals(Object o)
int	hashCode()
A	left() Accessor method for the left value of the pair.
static <A> Function<Pair<A,?>,A>	leftValue() Function for accessing the left value of pairs.
static <A,B> Pair<B,B>	map(Pair<A,A> aa, Function<A,B> f) Apply a function to both elements of an homogeneous pair.
static <A,B> Pair<A,B>	pair(A left, B right) Factory method for static Pair growth.
static <A,B> BiFunction<A,B,Pair<A,B>>	pairs() Factory method for a Pair factory function.
B	right() Accessor method for the right value of the pair.q
static <B> Function<Pair<?,B>,B>	rightValue() Function for accessing the right value of pairs.
String	toString()
static <A,B> Iterable<Pair<A,B>>	zip(Iterable<A> as, Iterable<B> bs) Zips two iterables into a single iterable that produces pairs.

Methods inherited from class java.lang.Object

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

Constructor Detail

Pair

public Pair(A left,
            B right)

Constructor for Pair.

Parameters:

left - value, cannot be null

right - value, cannot be null

Method Detail

pair

public static <A,B> Pair<A,B> pair(A left,
                                   B right)

Factory method for static Pair growth.

Type Parameters:

A - the left value type

B - the right value type

Parameters:

left - value, cannot be null

right - value, cannot be null

Returns:

the Pair containing the passed values

pairs

public static <A,B> BiFunction<A,B,Pair<A,B>> pairs()

Factory method for a Pair factory function.

Type Parameters:

A - the left value type

B - the right value type

Returns:

a function that constructs Pairs

leftValue

public static <A> Function<Pair<A,?>,A> leftValue()

Function for accessing the left value of pairs.

Type Parameters:

A - the left value type

Returns:

a Function that given a Pair returns the left side value

Since:

1.1

rightValue

public static <B> Function<Pair<?,B>,B> rightValue()

Function for accessing the right value of pairs.

Type Parameters:

B - the right value type

Returns:

a Function that given a Pair returns the right side value

Since:

1.1

ap

public static <A,B> Pair<B,B> ap(Pair<A,A> aa,
                                 Pair<Function<A,B>,Function<A,B>> ff)

Performs function application within an homogeneous pair (applicative functor pattern).

Parameters:

aa - an homogeneous pair

ff - The pair of functions to apply.

Returns:

A new pair after applying the given pair of functions through aa.

map

public static <A,B> Pair<B,B> map(Pair<A,A> aa,
                                  Function<A,B> f)

Apply a function to both elements of an homogeneous pair.

Parameters:

aa - an homogeneous pair

f - function to apply to both elements of aa

Returns:

A new pair after applying the function to aa elements.

zip

public static <A,B> Iterable<Pair<A,B>> zip(Iterable<A> as,
                                            Iterable<B> bs)

Zips two iterables into a single iterable that produces pairs.

Type Parameters:

A - LHS type

B - RHS type

Parameters:

as - left values

bs - right values

Returns:

an iterable of pairs, only as long as the shortest input iterable.

Since:

1.1

left

public A left()

Accessor method for the left value of the pair.

Returns:

a A object.

right

public B right()

Accessor method for the right value of the pair.q

Returns:

a B object.

toString

public String toString()

Overrides:

toString in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object