#region Assembly MediatR, Version=3.0.1.0, Culture=neutral, PublicKeyToken=null // C:\Users\jalbe\.nuget\packages\mediatr.0.1\lib\netstandard1.1\MediatR.dll #endregion  namespace MediatR {     public interface INotificationHandler<in TNotification> where TNotification : INotification     {         void Handle(TNotification notification);     } }

 INotificationHandler<RegisterNewCustomerCommand>,  INotificationHandler<UpdateCustomerCommand>,  INotificationHandler<RemoveCustomerCommand>

public class CustomerCommandHandler : CommandHandler,         INotificationHandler<RegisterNewCustomerCommand>,         INotificationHandler<UpdateCustomerCommand>,         INotificationHandler<RemoveCustomerCommand>     {         private readonly ICustomerRepository _customerRepository;         private readonly IMediatorHandler Bus;          public CustomerCommandHandler(ICustomerRepository customerRepository,                                       IUnitOfWork uow,                                       IMediatorHandler bus,                                       INotificationHandler<DomainNotification> notifications) : base(uow, bus, notifications)         {             _customerRepository = customerRepository;             Bus = bus;         }          public void Handle(RegisterNewCustomerCommand message)         {             if (!message.IsValid())             {                 NotifyValidationErrors(message);                 return;             }              var customer = new Customer(Guid.NewGuid(), message.Name, message.Email, message.BirthDate);              if (_customerRepository.GetByEmail(customer.Email) != null)             {                 Bus.RaiseEvent(new DomainNotification(message.MessageType, "The customer e-mail has already been taken."));                 return;             }              _customerRepository.Add(customer);              if (Commit())             {                 Bus.RaiseEvent(new CustomerRegisteredEvent(customer.Id, customer.Name, customer.Email, customer.BirthDate));             }         }          public void Handle(UpdateCustomerCommand message)         {             if (!message.IsValid())             {                 NotifyValidationErrors(message);                 return;             }              var customer = new Customer(message.Id, message.Name, message.Email, message.BirthDate);             var existingCustomer = _customerRepository.GetByEmail(customer.Email);              if (existingCustomer != null && existingCustomer.Id != customer.Id)             {                 if (!existingCustomer.Equals(customer))                 {                     Bus.RaiseEvent(new DomainNotification(message.MessageType, "The customer e-mail has already been taken."));                     return;                 }             }              _customerRepository.Update(customer);              if (Commit())             {                 Bus.RaiseEvent(new CustomerUpdatedEvent(customer.Id, customer.Name, customer.Email, customer.BirthDate));             }         }          public void Handle(RemoveCustomerCommand message)         {             if (!message.IsValid())             {                 NotifyValidationErrors(message);                 return;             }              _customerRepository.Remove(message.Id);              if (Commit())             {                 Bus.RaiseEvent(new CustomerRemovedEvent(message.Id));             }         }          public void Dispose()         {             _customerRepository.Dispose();         }      }

#region Assembly MediatR, Version=4.0.1.0, Culture=neutral, PublicKeyToken=null // C:\Users\jalbe\.nuget\packages\mediatr.0.1\lib\netstandard1.1\MediatR.dll #endregion  using System.Threading; using System.Threading.Tasks;  namespace MediatR {     public interface INotificationHandler<in TNotification> where TNotification : INotification     {         Task Handle(TNotification notification, CancellationToken cancellationToken);     } }

 public Task Handle(RegisterNewCustomerCommand notification, CancellationToken cancellationToken)         {             throw new NotImplementedException();         }          public Task Handle(UpdateCustomerCommand notification, CancellationToken cancellationToken)         {             throw new NotImplementedException();         }          public Task Handle(RemoveCustomerCommand notification, CancellationToken cancellationToken)         {             throw new NotImplementedException();                    }

public Task Handle(RemoveCustomerCommand notification, CancellationToken cancellationToken)         {             if (!message.IsValid())             {                 NotifyValidationErrors(message);                 return;             }              _customerRepository.Remove(message.Id);              if (Commit())             {                 Bus.RaiseEvent(new CustomerRemovedEvent(message.Id));             }         }