// patterns/PaperScissorsRock.java

// (c)2021 MindView LLC: see Copyright.txt

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// Demonstration of multiple dispatching.

import java.util.*;

import java.util.function.*;

import java.util.stream.*;

import enums.Outcome;

import static enums.Outcome.*;

import enums.Item;

import enums.Paper;

import enums.Scissors;

import enums.Rock;

import onjava.*;

import static onjava.Tuple.*;

class ItemFactory {

static List<Supplier<Item>> items =

Arrays.asList(

Scissors::new, Paper::new, Rock::new);

static final int SZ = items.size();

private static SplittableRandom rand =

new SplittableRandom(47);

public static Item newItem() {

return items.get(rand.nextInt(SZ)).get();

}

public static Tuple2<Item,Item> newPair() {

return tuple(newItem(), newItem());

}

}

class Compete {

public static Outcome match(Tuple2<Item,Item> p) {

System.out.print(p.a1 + " -> " + p.a2 + " : ");

return p.a1.compete(p.a2);

}

}

public class PaperScissorsRock {

public static void main(String[] args) {

Stream.generate(ItemFactory::newPair)

.limit(20)

.map(Compete::match)

.forEach(System.out::println);

}

}

/* Output:

Scissors -> Rock : LOSE

Scissors -> Paper : WIN

Rock -> Paper : LOSE

Rock -> Rock : DRAW

Rock -> Paper : LOSE

Paper -> Scissors : LOSE

Rock -> Paper : LOSE

Scissors -> Scissors : DRAW

Scissors -> Rock : LOSE

Scissors -> Paper : WIN

Scissors -> Rock : LOSE

Paper -> Scissors : LOSE

Rock -> Rock : DRAW

Scissors -> Scissors : DRAW

Paper -> Paper : DRAW

Scissors -> Paper : WIN

Scissors -> Rock : LOSE

Scissors -> Paper : WIN

Rock -> Paper : LOSE

Rock -> Scissors : WIN

*/