com.net2plan.utils

Class Pair<A,B>

java.lang.Object

com.net2plan.utils.Pair<A,B>

Type Parameters:

A - Class type for the first element

B - Class type for the second element

All Implemented Interfaces:

Comparable<Object>

public class Pair<A,B>
extends Object
implements Comparable<Object>

A tuple consisting of two elements. There is no restriction on the type of the objects that may be stored.

Example:

Map<String, Object> map = new LinkedHashMap<>();
map.put("parameter", "value");
Integer number = new Integer(3);

Pair<Map<String, Object>, Integer> data = new Pair<>(map, number);

...

Map<String, Object> myMap = data.getFirst();
Integer myNumber = data.getSecond();

Author:

Pablo Pavon-Marino, Jose-Luis Izquierdo-Zaragoza

See Also:

Triple, Quadruple, Quintuple

Constructor Summary

Constructors

Constructor and Description
Pair(A a, B b, boolean isModifiable) Default constructor.

Method Summary

Modifier and Type	Method and Description
int	compareTo(Object o)
boolean	equals(Object o) Indicates whether some other object is "equal to" this one.
A	getFirst() Returns the first element from this pair.
B	getSecond() Returns the second element from this pair.
int	hashCode() Returns a hash code value for the object.
boolean	isModifiable() Indicates whether or not elements from the pair can be changed after initialization.
static <A,B> Pair<A,B>	of(A a, B b) This factory allows a pair to be created using inference to obtain the generic types.
void	setFirst(A a) Sets the first element from this pair.
void	setSecond(B b) Sets the second element from this pair.
String	toString() Returns a String representation of this pair using the format (first, second).
static <A,B> Pair<A,B>	unmodifiableOf(A a, B b) This factory allows an unmodifiable pair to be created using inference to obtain the generic types.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Pair

public Pair(A a,
            B b,
            boolean isModifiable)

Default constructor.

Parameters:

a - The first element, may be null

b - The second element, may be null

isModifiable - Indicates whether or not the elements can be changed after initialization

Method Detail

compareTo

public int compareTo(Object o)

Specified by:

compareTo in interface Comparable<Object>

equals

public boolean equals(Object o)

Indicates whether some other object is "equal to" this one.

Overrides:

equals in class Object

Parameters:

o - Reference object with which to compare

Returns:

true if this object is the same as the o argument; false otherwise

getFirst

public A getFirst()

Returns the first element from this pair.

Returns:

The first element from this pair

getSecond

public B getSecond()

Returns the second element from this pair.

Returns:

The second element from this pair

hashCode

public int hashCode()

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap.

Overrides:

hashCode in class Object

Returns:

Hash code value for this object

isModifiable

public boolean isModifiable()

Indicates whether or not elements from the pair can be changed after initialization.

Returns:

true if the element can be changed. Otherwise, false

of

public static <A,B> Pair<A,B> of(A a,
                                 B b)

This factory allows a pair to be created using inference to obtain the generic types.

Type Parameters:

A - Class type for the first element

B - Class type for the second element

Parameters:

a - The first element, may be null

b - The second element, may be null

Returns:

A pair formed from two parameters

setFirst

public void setFirst(A a)

Sets the first element from this pair.

Parameters:

a - The first element, may be null

setSecond

public void setSecond(B b)

Sets the second element from this pair.

Parameters:

b - The second element, may be null

toString

public String toString()

Returns a String representation of this pair using the format (first, second).

Overrides:

toString in class Object

Returns:

A String representation of this pair

unmodifiableOf

public static <A,B> Pair<A,B> unmodifiableOf(A a,
                                             B b)

This factory allows an unmodifiable pair to be created using inference to obtain the generic types.

Type Parameters:

A - Class type for the first element

B - Class type for the second element

Parameters:

a - The first element, may be null

b - The second element, may be null

Returns:

An unmodifiable pair formed from two parameters