// concurrent/Batter.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.concurrent.*;
import onjava.Nap;
public class Batter {
static class Eggs {}
static class Milk {}
static class Sugar {}
static class Flour {}
static T prepare(T ingredient) {
new Nap(0.1);
return ingredient;
}
static CompletableFuture prep(T ingredient) {
return CompletableFuture
.completedFuture(ingredient)
.thenApplyAsync(Batter::prepare);
}
public static CompletableFuture mix() {
CompletableFuture eggs = prep(new Eggs());
CompletableFuture milk = prep(new Milk());
CompletableFuture sugar = prep(new Sugar());
CompletableFuture flour = prep(new Flour());
CompletableFuture
.allOf(eggs, milk, sugar, flour)
.join();
new Nap(0.1); // Mixing time
return
CompletableFuture.completedFuture(new Batter());
}
}