org.apache.commons.lang3.tuple

Class Triple<L,M,R>

java.lang.Object

org.apache.commons.lang3.tuple.Triple<L,M,R>

Type Parameters:

L - the left element type

M - the middle element type

R - the right element type

All Implemented Interfaces:

java.io.Serializable, java.lang.Comparable<Triple<L,M,R>>

Direct Known Subclasses:

ImmutableTriple, MutableTriple

public abstract class Triple<L,M,R>
extends java.lang.Object
implements java.lang.Comparable<Triple<L,M,R>>, java.io.Serializable

A triple consisting of three elements.

This class is an abstract implementation defining the basic API. It refers to the elements as 'left', 'middle' and 'right'.

Subclass implementations may be mutable or immutable. However, there is no restriction on the type of the stored objects that may be stored. If mutable objects are stored in the triple, then the triple itself effectively becomes mutable.

Since:

3.2

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
static Triple<?,?,?>[]	EMPTY_ARRAY An empty array.

Constructor Summary

Constructors

Constructor and Description
Triple()

Method Summary

Modifier and Type	Method and Description
int	compareTo(Triple<L,M,R> other) Compares the triple based on the left element, followed by the middle element, finally the right element.
static <L,M,R> Triple<L,M,R>[]	emptyArray() Returns the empty array singleton that can be assigned without compiler warning.
boolean	equals(java.lang.Object obj) Compares this triple to another based on the three elements.
abstract L	getLeft() Gets the left element from this triple.
abstract M	getMiddle() Gets the middle element from this triple.
abstract R	getRight() Gets the right element from this triple.
int	hashCode() Returns a suitable hash code.
static <L,M,R> Triple<L,M,R>	of(L left, M middle, R right) Obtains an immutable triple of three objects inferring the generic types.
static <L,M,R> Triple<L,M,R>	ofNonNull(L left, M middle, R right) Obtains an immutable triple of three non-null objects inferring the generic types.
java.lang.String	toString() Returns a String representation of this triple using the format ($left,$middle,$right).
java.lang.String	toString(java.lang.String format) Formats the receiver using the given format.

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Field Detail

EMPTY_ARRAY

public static final Triple<?,?,?>[] EMPTY_ARRAY

An empty array.

Consider using emptyArray() to avoid generics warnings.

Since:

3.10.

Constructor Detail

Triple

public Triple()

Method Detail

emptyArray

public static <L,M,R> Triple<L,M,R>[] emptyArray()

Returns the empty array singleton that can be assigned without compiler warning.

Type Parameters:

L - the left element type

M - the middle element type

R - the right element type

Returns:

the empty array singleton that can be assigned without compiler warning.

Since:

3.10.

of

public static <L,M,R> Triple<L,M,R> of(L left,
                                       M middle,
                                       R right)

Obtains an immutable triple of three objects inferring the generic types.

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

Type Parameters:

L - the left element type

M - the middle element type

R - the right element type

Parameters:

left - the left element, may be null

middle - the middle element, may be null

right - the right element, may be null

Returns:

a triple formed from the three parameters, not null

ofNonNull

public static <L,M,R> Triple<L,M,R> ofNonNull(L left,
                                              M middle,
                                              R right)

Obtains an immutable triple of three non-null objects inferring the generic types.

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

Type Parameters:

L - the left element type

M - the middle element type

R - the right element type

Parameters:

left - the left element, may not be null

middle - the middle element, may not be null

right - the right element, may not be null

Returns:

a triple formed from the three parameters, not null

Throws:

java.lang.NullPointerException - if any input is null

Since:

3.13.0

compareTo

public int compareTo(Triple<L,M,R> other)

Compares the triple based on the left element, followed by the middle element, finally the right element. The types must be Comparable.

Specified by:

compareTo in interface java.lang.Comparable<Triple<L,M,R>>

Parameters:

other - the other triple, not null

Returns:

negative if this is less, zero if equal, positive if greater

equals

public boolean equals(java.lang.Object obj)

Compares this triple to another based on the three elements.

Overrides:

equals in class java.lang.Object

Parameters:

obj - the object to compare to, null returns false

Returns:

true if the elements of the triple are equal

getLeft

public abstract L getLeft()

Gets the left element from this triple.

Returns:

the left element, may be null

getMiddle

public abstract M getMiddle()

Gets the middle element from this triple.

Returns:

the middle element, may be null

getRight

public abstract R getRight()

Gets the right element from this triple.

Returns:

the right element, may be null

hashCode

public int hashCode()

Returns a suitable hash code.

Overrides:

hashCode in class java.lang.Object

Returns:

the hash code

toString

public java.lang.String toString()

Returns a String representation of this triple using the format ($left,$middle,$right).

Overrides:

toString in class java.lang.Object

Returns:

a string describing this object, not null

toString

public java.lang.String toString(java.lang.String format)

Formats the receiver using the given format.

This uses Formattable to perform the formatting. Three variables may be used to embed the left and right elements. Use %1$s for the left element, %2$s for the middle and %3$s for the right element. The default format used by toString() is (%1$s,%2$s,%3$s).

Parameters:

format - the format string, optionally containing %1$s, %2$s and %3$s, not null

Returns:

the formatted string, not null