import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public InventoryServiceImpl(PersistentEntityRegistry registry, BasketService basketService) {
    this.registry = registry;
    this.basketService = basketService;
    registry.register(InventoryEntity.class);

    // this solution is naïve on the approach and wrong altogether in the implementation
    //  a) when applying a filter in the akka stream, the message is missaligned with the offset
    //  b) updating the inventory should be handled in a way that if a product is out of stock an event is
    //     raised and the shppoing-user is notified so she can decide what to do. Also, the out-of-stock product
    //     must be reimbursed. All this corrective actions are not implemented, on the contrary: when the
    //     InventoryEntity detects there's not enough stock for a given Deacrease operation an exception is throw.
    //     Instead, an event other downstream services can listen to would be more appropriate.
    // I will try to get (a) fixed on further versions of this workshop.
    //
    basketService.basketEvents().subscribe().atLeastOnce(
            Flow.<BasketEvent>create()
                    .filter(b -> b instanceof BasketEvent.BasketCheckedOut)
                    .mapConcat(basketEvent -> {
                        BasketEvent.BasketCheckedOut event = (BasketEvent.BasketCheckedOut) basketEvent;
                        return event.getBasket().getItems();
                    })
                    .mapAsync(1, basketItem ->
                            refFor(basketItem.getId())
                                    .ask(new DecreaseInventory(basketItem.getId(), basketItem.getCount()))
                    ).map(ignored -> Done.getInstance())
    );

}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public FriendServiceImpl(PersistentEntityRegistry persistentEntities, ReadSide readSide,
    CassandraSession db) {
  this.persistentEntities = persistentEntities;
  this.db = db;

  persistentEntities.register(FriendEntity.class);
  readSide.register(FriendEventProcessor.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public ChirpServiceImpl(PersistentEntityRegistry persistentEntities, ChirpTopic topic, ChirpRepository chirps) {
    this.persistentEntities = persistentEntities;
    this.topic = topic;
    this.chirps = chirps;

    persistentEntities.register(ChirpTimelineEntity.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
/**
 * Constructor with the relevant infrastructure elements injected.
 *
 * @param topics
 * @param persistentEntityRegistry
 * @param readSide
 * @param db
 */
@Inject
public RegistrationServiceImpl(PubSubRegistry topics, PersistentEntityRegistry persistentEntityRegistry, CassandraReadSide readSide,
                               CassandraSession db) {
    this.persistentEntityRegistry = persistentEntityRegistry;
    this.topics = topics;
    this.db = db;
    persistentEntityRegistry.register(CargoEntity.class);
    readSide.register(CargoEventProcessor.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public FriendServiceImpl(PersistentEntityRegistry persistentEntities, CassandraReadSide readSide,
    CassandraSession db) {
  this.persistentEntities = persistentEntities;
  this.db = db;

  persistentEntities.register(FriendEntity.class);
  readSide.register(FriendEventProcessor.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public FavoriteServiceImpl(PersistentEntityRegistry persistentEntities,
                           CassandraReadSide readSide,
                           CassandraSession db) {
    this.persistentEntities = persistentEntities;
    this.persistentEntities.register(FavoriteEntity.class);
    this.db = db;

    readSide.register(FavoriteEventProcessor.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public BasketServiceImpl(PersistentEntityRegistry registry) {
    this.registry = registry;
    registry.register(com.example.basket.impl.BasketEntity.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public HelloServiceImpl(PersistentEntityRegistry persistentEntityRegistry) {
  this.persistentEntityRegistry = persistentEntityRegistry;
  persistentEntityRegistry.register(HelloEntity.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public ShippingServiceImpl(PersistentEntityRegistry persistentEntityRegistry, RegistrationService registrationService) {
    this.persistentEntityRegistry = persistentEntityRegistry;
    this.registrationService = registrationService;
    persistentEntityRegistry.register(ItineraryEntity.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public BlogServiceImpl(final PersistentEntityRegistry registry) {
    this.registry = registry;
    registry.register(BlogEntity.class);
}
 

import com.lightbend.lagom.javadsl.persistence.PersistentEntityRegistry; //导入依赖的package包/类
@Inject
public HelloServiceImpl(PersistentEntityRegistry persistentEntityRegistry) {
    this.persistentEntityRegistry = persistentEntityRegistry;
    persistentEntityRegistry.register(HelloEntity.class);
}