Currying in Java

SampleCurrying.java

import java.util.function.Function;

import static java.lang.String.format;

class SampleCurrying {

    public static void main(String[] args) {

        Fx2<Integer, Integer, Integer> add = (x, y) -> x + y;
        System.out.println(format("Non curried add function of 2 arity result: %s", add.apply(2, 3)));

        Function<Integer, Function<Integer, Integer>> curriedAdd = Currying.curry(add);
        System.out.println(format("Add function curried with value 2 then 3: %s", curriedAdd.apply(2).apply(3)));

        Fx3<Integer, Integer, String, String> descriptiveAdd = (x, y, z) -> z + (x + y);
        Function<Integer, Function<Integer, Function<String, String>>> curriedDescriptiveAdd =
                Currying.curry(descriptiveAdd);

        Function<String, String> describe5 = curriedDescriptiveAdd
                .apply(2)
                .apply(3);
        System.out.println(describe5.apply("The result is: "));
    }

    /**
     * Function with arity of 2
     * @param <I1> type of first input
     * @param <I2> type of second input
     * @param <O> type of output
     */
    @FunctionalInterface
    public interface Fx2<I1, I2, O> {

        /**
         * Execute this function
         * @param inputOne first input
         * @param inputTwo second input
         * @return output of this function
         */
        O apply(I1 inputOne, I2 inputTwo);
    }

    /**
     * Function with arity of 3
     * @param <I1> type of first input
     * @param <I2> type of second input
     * @param <I3> type of third input
     * @param <O> type of output
     */
    @FunctionalInterface
    public interface Fx3<I1, I2, I3, O> {

        /**
         * Execute this function
         * @param inputOne first input
         * @param inputTwo second input
         * @param inputThree third input
         * @return output of this function
         */
        O apply(I1 inputOne, I2 inputTwo, I3 inputThree);
    }

    public static class Currying {

        public static <I1, I2, I3, O> Function<I1, Function<I2, Function<I3, O>>> curry(Fx3<I1, I2, I3, O> f){
            return i1 -> i2 -> i3 -> f.apply(i1, i2, i3);
        }

        public static <I1, I2, O> Function<I1, Function<I2, O>> curry(Fx2<I1, I2, O> f){
            return i1 -> i2 -> f.apply(i1, i2);
        }
    }
}