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Functional patterns for Java

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package com.jnape.palatable.lambda.semigroup.builtin;

import com.jnape.palatable.lambda.functions.Fn1;
import com.jnape.palatable.lambda.functions.specialized.SemigroupFactory;
import com.jnape.palatable.lambda.semigroup.Semigroup;

import java.util.Comparator;

import static com.jnape.palatable.lambda.functions.builtin.fn3.LTWith.ltWith;

/**
 * Given a comparator for some type A, produce a {@link Semigroup} over A that chooses
 * between two values x and y via the following rules:
 * 
 * If x is strictly less than y in terms of B, return y
 * Otherwise, return x
 * 
 *
 * @param  the value type
 * @see Max
 * @see MaxBy
 * @see MinWith
 */
public final class MaxWith implements SemigroupFactory, A> {

    private static final MaxWith INSTANCE = new MaxWith<>();

    private MaxWith() {
    }

    @SuppressWarnings("unchecked")
    public static  MaxWith maxWith() {
        return (MaxWith) INSTANCE;
    }

    public static  Semigroup maxWith(Comparator compareFn) {
        return MaxWith.maxWith().apply(compareFn);
    }

    public static  Fn1 maxWith(Comparator compareFn, A x) {
        return MaxWith.maxWith(compareFn).apply(x);
    }

    public static  A maxWith(Comparator compareFn, A x, A y) {
        return maxWith(compareFn, x).apply(y);
    }

    @Override
    public Semigroup checkedApply(Comparator comparator) {
        return (x, y) -> ltWith(comparator, y, x) ? y : x;
    }
}