AsyncDatastoreService (Google App Engine API for Java)

Interface AsyncDatastoreService

  • All Superinterfaces:
    All Known Implementing Classes:

    public interface AsyncDatastoreService
    extends BaseDatastoreService
    An asynchronous version of DatastoreService. All methods return immediately and provide Futures as their return values.

    The key difference between implementations of AsyncDatastoreService and implementations of DatastoreService is that async implementations do not perform implicit transaction management. The reason is that implicit transaction management requires automatic commits of some transactions, and without some sort of callback mechanism there is no way to determine that a put/get/delete that has been implicitly enrolled in a transaction is complete and therefore ready to be committed. See ImplicitTransactionManagementPolicy for more information.