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Intuitive Event-Driven Reactive Programming Library for Java

There is a newer version: 2.8.0

package io.smallrye.mutiny.tuples;

import java.util.Arrays;
import java.util.List;
import java.util.Objects;
import java.util.function.Function;

/**
 * A tuple containing two items.
 *
 * @param  The type of the first item
 * @param  The type of the second item
 */
public class Tuple2 implements Tuple {

    final L item1;
    final R item2;

    protected Tuple2(L left, R right) {
        this.item1 = left;
        this.item2 = right;
    }

    public static  Tuple2 of(L l, R r) {
        return new Tuple2<>(l, r);
    }

    /**
     * Gets the first item.
     *
     * @return The first item, can be {@code null}
     */
    public L getItem1() {
        return item1;
    }

    /**
     * Gets the second item.
     *
     * @return The second item, can be {@code null}
     */
    public R getItem2() {
        return item2;
    }

    /**
     * Applies a mapper function to the left (item1) part of this {@link Tuple2} to produce a new {@link Tuple2}.
     * The right part (item2) is not modified.
     *
     * @param mapper the mapping {@link Function} for the left item
     * @param  the new type for the left item
     * @return the new {@link Tuple2}
     */
    public  Tuple2 mapItem1(Function mapper) {
        return Tuple2.of(mapper.apply(item1), item2);
    }

    /**
     * Applies a mapper function to the right part (item2) of this {@link Tuple2} to produce a new {@link Tuple2}.
     * The left (item1) part is not modified.
     *
     * @param mapper the mapping {@link Function} for the right item
     * @param  the new type for the right item
     * @return the new {@link Tuple2}
     */
    public  Tuple2 mapItem2(Function mapper) {
        return Tuple2.of(item1, mapper.apply(item2));
    }

    @Override
    public Object nth(int index) {
        assertIndexInBounds(index);
        if (index == 0) {
            return item1;
        }
        return item2;
    }

    protected void assertIndexInBounds(int index) {
        if (index < 0 || index >= size()) {
            throw new IndexOutOfBoundsException(
                    "Cannot retrieve item at position " + index + ", size is " + size());
        }
    }

    @Override
    public List