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package jdk.internal.vm.compiler.collections;

import java.util.Objects;

Utility class representing a pair of values.
Since:19.0
/** * Utility class representing a pair of values. * * @since 19.0 */
public final class Pair<L, R> { private static final Pair<Object, Object> EMPTY = new Pair<>(null, null); private final L left; private final R right;
Returns an empty pair.
Since:19.0
/** * Returns an empty pair. * * @since 19.0 */
@SuppressWarnings("unchecked") public static <L, R> Pair<L, R> empty() { return (Pair<L, R>) EMPTY; }
Constructs a pair with its left value being left, or returns an empty pair if left is null.
Returns:the constructed pair or an empty pair if left is null.
Since:19.0
/** * Constructs a pair with its left value being {@code left}, or returns an empty pair if * {@code left} is null. * * @return the constructed pair or an empty pair if {@code left} is null. * @since 19.0 */
public static <L, R> Pair<L, R> createLeft(L left) { if (left == null) { return empty(); } else { return new Pair<>(left, null); } }
Constructs a pair with its right value being right, or returns an empty pair if right is null.
Returns:the constructed pair or an empty pair if right is null.
Since:19.0
/** * Constructs a pair with its right value being {@code right}, or returns an empty pair if * {@code right} is null. * * @return the constructed pair or an empty pair if {@code right} is null. * @since 19.0 */
public static <L, R> Pair<L, R> createRight(R right) { if (right == null) { return empty(); } else { return new Pair<>(null, right); } }
Constructs a pair with its left value being left, and its right value being right, or returns an empty pair if both inputs are null.
Returns:the constructed pair or an empty pair if both inputs are null.
Since:19.0
/** * Constructs a pair with its left value being {@code left}, and its right value being * {@code right}, or returns an empty pair if both inputs are null. * * @return the constructed pair or an empty pair if both inputs are null. * @since 19.0 */
public static <L, R> Pair<L, R> create(L left, R right) { if (right == null && left == null) { return empty(); } else { return new Pair<>(left, right); } } private Pair(L left, R right) { this.left = left; this.right = right; }
Returns the left value of this pair.
Since:19.0
/** * Returns the left value of this pair. * * @since 19.0 */
public L getLeft() { return left; }
Returns the right value of this pair.
Since:19.0
/** * Returns the right value of this pair. * * @since 19.0 */
public R getRight() { return right; }
{@inheritDoc}
Since:19.0
/** * {@inheritDoc} * * @since 19.0 */
@Override public int hashCode() { return Objects.hashCode(left) + 31 * Objects.hashCode(right); }
{@inheritDoc}
Since:19.0
/** * {@inheritDoc} * * @since 19.0 */
@SuppressWarnings("unchecked") @Override public boolean equals(Object obj) { if (obj == this) { return true; } if (obj instanceof Pair) { Pair<L, R> pair = (Pair<L, R>) obj; return Objects.equals(left, pair.left) && Objects.equals(right, pair.right); } return false; }
{@inheritDoc}
Since:19.0
/** * {@inheritDoc} * * @since 19.0 */
@Override public String toString() { return String.format("(%s, %s)", left, right); } }