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 * (the "License"); you may not use this file except in compliance with
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 *      http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.commons.lang3.tuple;

import java.io.Serializable;
import java.util.Objects;

import org.apache.commons.lang3.builder.CompareToBuilder;

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.

Type parameters:
  • <L> – the left element type
  • <M> – the middle element type
  • <R> – the right element type
Since:3.2
/** * <p>A triple consisting of three elements.</p> * * <p>This class is an abstract implementation defining the basic API. * It refers to the elements as 'left', 'middle' and 'right'.</p> * * <p>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.</p> * * @param <L> the left element type * @param <M> the middle element type * @param <R> the right element type * * @since 3.2 */
public abstract class Triple<L, M, R> implements Comparable<Triple<L, M, R>>, Serializable {
Serialization version
/** Serialization version */
private static final long serialVersionUID = 1L;

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

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

Params:
  • left – the left element, may be null
  • middle – the middle element, may be null
  • right – the right element, may be null
Type parameters:
  • <L> – the left element type
  • <M> – the middle element type
  • <R> – the right element type
Returns:a triple formed from the three parameters, not null
/** * <p>Obtains an immutable triple of from three objects inferring the generic types.</p> * * <p>This factory allows the triple to be created using inference to * obtain the generic types.</p> * * @param <L> the left element type * @param <M> the middle element type * @param <R> the right element type * @param left the left element, may be null * @param middle the middle element, may be null * @param right the right element, may be null * @return a triple formed from the three parameters, not null */
public static <L, M, R> Triple<L, M, R> of(final L left, final M middle, final R right) { return new ImmutableTriple<>(left, middle, right); } //-----------------------------------------------------------------------

Gets the left element from this triple.

Returns:the left element, may be null
/** * <p>Gets the left element from this triple.</p> * * @return the left element, may be null */
public abstract L getLeft();

Gets the middle element from this triple.

Returns:the middle element, may be null
/** * <p>Gets the middle element from this triple.</p> * * @return the middle element, may be null */
public abstract M getMiddle();

Gets the right element from this triple.

Returns:the right element, may be null
/** * <p>Gets the right element from this triple.</p> * * @return the right element, may be null */
public abstract R getRight(); //-----------------------------------------------------------------------

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

Params:
  • other – the other triple, not null
Returns:negative if this is less, zero if equal, positive if greater
/** * <p>Compares the triple based on the left element, followed by the middle element, * finally the right element. * The types must be {@code Comparable}.</p> * * @param other the other triple, not null * @return negative if this is less, zero if equal, positive if greater */
@Override public int compareTo(final Triple<L, M, R> other) { return new CompareToBuilder().append(getLeft(), other.getLeft()) .append(getMiddle(), other.getMiddle()) .append(getRight(), other.getRight()).toComparison(); }

Compares this triple to another based on the three elements.

Params:
  • obj – the object to compare to, null returns false
Returns:true if the elements of the triple are equal
/** * <p>Compares this triple to another based on the three elements.</p> * * @param obj the object to compare to, null returns false * @return true if the elements of the triple are equal */
@Override public boolean equals(final Object obj) { if (obj == this) { return true; } if (obj instanceof Triple<?, ?, ?>) { final Triple<?, ?, ?> other = (Triple<?, ?, ?>) obj; return Objects.equals(getLeft(), other.getLeft()) && Objects.equals(getMiddle(), other.getMiddle()) && Objects.equals(getRight(), other.getRight()); } return false; }

Returns a suitable hash code.

Returns:the hash code
/** * <p>Returns a suitable hash code.</p> * * @return the hash code */
@Override public int hashCode() { return (getLeft() == null ? 0 : getLeft().hashCode()) ^ (getMiddle() == null ? 0 : getMiddle().hashCode()) ^ (getRight() == null ? 0 : getRight().hashCode()); }

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

Returns:a string describing this object, not null
/** * <p>Returns a String representation of this triple using the format {@code ($left,$middle,$right)}.</p> * * @return a string describing this object, not null */
@Override public String toString() { return "(" + getLeft() + "," + getMiddle() + "," + getRight() + ")"; }

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).

Params:
  • format – the format string, optionally containing %1$s, %2$s and %3$s, not null
Returns:the formatted string, not null
/** * <p>Formats the receiver using the given format.</p> * * <p>This uses {@link java.util.Formattable} to perform the formatting. Three variables may * be used to embed the left and right elements. Use {@code %1$s} for the left * element, {@code %2$s} for the middle and {@code %3$s} for the right element. * The default format used by {@code toString()} is {@code (%1$s,%2$s,%3$s)}.</p> * * @param format the format string, optionally containing {@code %1$s}, {@code %2$s} and {@code %3$s}, not null * @return the formatted string, not null */
public String toString(final String format) { return String.format(format, getLeft(), getMiddle(), getRight()); } }