// concurrent/CompletablePizza.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.

import java.util.*;

import java.util.concurrent.*;

import java.util.stream.*;

import onjava.Timer;

public class CompletablePizza {

static final int QUANTITY = 5;

public static CompletableFuture<Pizza>

makeCF(Pizza za) {

return CompletableFuture

.completedFuture(za)

.thenApplyAsync(Pizza::roll)

.thenApplyAsync(Pizza::sauce)

.thenApplyAsync(Pizza::cheese)

.thenApplyAsync(Pizza::toppings)

.thenApplyAsync(Pizza::bake)

.thenApplyAsync(Pizza::slice)

.thenApplyAsync(Pizza::box);

}

public static void

show(CompletableFuture<Pizza> cf) {

try {

System.out.println(cf.get());

} catch(Exception e) {

throw new RuntimeException(e);

}

}

public static void main(String[] args) {

Timer timer = new Timer();

List<CompletableFuture<Pizza>> pizzas =

IntStream.range(0, QUANTITY)

.mapToObj(Pizza::new)

.map(CompletablePizza::makeCF)

.collect(Collectors.toList());

System.out.println(timer.duration());

pizzas.forEach(CompletablePizza::show);

System.out.println(timer.duration());

}

}

/* Output:

98

Pizza 1: ROLLED

Pizza 3: ROLLED

Pizza 4: ROLLED

Pizza 2: ROLLED

Pizza 0: ROLLED

Pizza 1: SAUCED

Pizza 2: SAUCED

Pizza 3: SAUCED

Pizza 0: SAUCED

Pizza 4: SAUCED

Pizza 2: CHEESED

Pizza 0: CHEESED

Pizza 3: CHEESED

Pizza 1: CHEESED

Pizza 4: CHEESED

Pizza 2: TOPPED

Pizza 4: TOPPED

Pizza 1: TOPPED

Pizza 3: TOPPED

Pizza 0: TOPPED

Pizza 0: BAKED

Pizza 4: BAKED

Pizza 1: BAKED

Pizza 3: BAKED

Pizza 2: BAKED

Pizza 3: SLICED

Pizza 1: SLICED

Pizza 2: SLICED

Pizza 4: SLICED

Pizza 0: SLICED

Pizza 0: BOXED

Pizza 2: BOXED

Pizza 4: BOXED

Pizza 1: BOXED

Pizza0: complete

Pizza1: complete

Pizza2: complete

Pizza 3: BOXED

Pizza3: complete

Pizza4: complete

1762

*/