Factory or service template or injection method?

Question

I am currently thinking about which template should I solve the following problem.

I have an object called IdentificationRequest. This object is used to determine a Personby some criteria.

public class IdentificationRequest
{
     public IdentificationCriteria Criteria;
     public Person IdentifiedPerson;

     protected internal virtual void RedirectToManualIdentification()
     {
        ChangeState(IdentificationRequestState.ManualIdentificationRequested);
     }

     public virtual void StartManualIdentification()
     {
        ChangeState(IdentificationRequestState.ManualIdentificationInProgress);
     }

     public virtual void AssignIdentifiedPerson(Person person)
     {
        identifiedPerson = person;
        ChangeState(IdentificationRequestState.IdentificationFinished);       
     }
}

public class IdentificationCriteria
{
     public string Name;
}

This is a simplified example. The real world IdentificationRequestcontains much more information as well IdentificationCriteria.

Thus, basically the client creates IdentificationRequestwith it IdentificationCriteria, and then you need to identify the correct one Person. For this, the criteria must be transferred to the persistence level to check if there is a person in the database that matches the criteria. If no person can be found, then interaction with the person is required to assign the correct Personrequest.

. :

    public class IdentificationService : IIdentificationService
        {
            private readonly IPersonRepository personRepository ;
            private readonly IIdentificationRequestRepository identificationRequestRepository;

            public IdentificationService(IPersonRepository personRepository )
            {
                this.personRepository = personRepository ;
            }

            public bool IdentifyPerson(IdentificationRequest identificationRequest)
            {
                var matches = personRepository.FindByIdentificationCriteria(identificationRequest.Criteria);

                // some additional post analysis of the matches returned from the persistence layer
                var criteriaAnalyzer = new IdentificationCriteriaAnalyzer(identificationRequest.Criteria);
                var uniqueMatch = criteriaAnalyzer.TryIdentify(matches);

                if(uniqueMatch != null)
                {
                    identificationRequest.AssignIdentifiedPerson(uniqueMatch);
                    return true;
                }
                else
                {
                    identificationRequest.RedirectToManualIdentification();
                    return false;
                }            
            }
        }

. : ? factory, , , :

public class IdentificationRequestFactory
{
    private readonly IPersonRepository personRepository;

    public IdentificationRequestFactory(IPersonRepository personRepository)
    {
        this.personRepository = personRepository;
    }

    public IdentificationRequest Create(IdentificationCriteria identificationCriteria)
    {
        var request = new IdentificationRequest(identificationCriteria);

        var matches = personRepository.FindByIdentificationCriteria(identificationRequest.Criteria);
        var criteriaAnalyzer = new IdentificationCriteriaAnalyzer(identificationRequest.Criteria);
        var uniqueMatch = criteriaAnalyzer.TryIdentify(matches);

        if(uniqueMatch != null)
        {
            identificationRequest.AssignIdentifiedPerson(uniqueMatch);

        }
        else
        {
            identificationRequest.RedirectToManualIdentification();

        }

        return request;
    }
}

, IdentificationRequest factory, , .

IdentificationRequest , , :

public class IdentificationRequest
{
    public IdentificationCriteria Criteria;
    public Person IdentifiedPerson;

    public void Identify(IPersonRepository personRepository)
    {
        // identification logic here
    }
}

.

? ? ?

!

, , ? ?

public class IdentificationCommandFactory
{
    private readonly IPersonRepository personRepository;

    public IdentificationCommandFactory(IPersonRepository personRepository)
    {

        this.personRepository = personRepository;
    }

    public IIdentificationCommand Create(IdentificationRequest identificationRequest)
    {
        var matches = personRepository.FindByIdentificationCriteria(identificationRequest);
        var criteriaAnalyzer = new IdentificationCriteriaAnalyzer(identificationRequest);
        var uniqueMatch = criteriaAnalyzer.TryIdentify(matches);

        if(uniqueMatch != null)
        {                
            return new AssignIdentifiedPersonCommand(identificationRequest, uniqueMatch);
        }
        else
        {                
            return new RedirectToManualIdentificationCommand(identificationRequest);
        }    
    }

}

public interface IIdentificationCommand
{
    void Execute();
}

public class RedirectToManualIdentificationCommand : IIdentificationCommand
{
    private readonly IdentificationRequest identificationRequest;

    public RedirectToManualIdentificationCommand(IdentificationRequest identificationRequest)
    {
        this.identificationRequest = identificationRequest;
    }

    public void Execute()
    {
        identificationRequest.RedirectToManualIdentification();
    }
}

public class AssignIdentifiedPersonCommand : IIdentificationCommand
{
    private readonly IdentificationRequest identificationRequest;
    private readonly Person personIdentified;

    public AssignIdentifiedPersonCommand(IdentificationRequest identificationRequest, Person personIdentified)
    {
        this.identificationRequest = identificationRequest;
        this.personIdentified = personIdentified;
    }

    public void Execute()
    {
        identificationRequest.AssignIdentifiedPerson(personIdentified);
    }
 }

:

    var identificationCommandFactory = new IdentificationCommandFactory(personRepository);

    var command = identificationCommandFactory.Create(request);

    command.Execute();

Answer 1

. (http://msdn.microsoft.com/en-us/magazine/cc163962.aspx)

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Answer 2

IdentificationCriteria IdentificationCriteriaAnalyzer , , .

, IdentificationRequest - / Person?

API -.

, , , IdentificationCriteria - Command. Factory.

public interface IIdentificationCommandFactory
{
    IIdentificationCommand Create(IdentificationCriteria spec);
}

, repostiry ( IdentificationCriteriaAnalyzer) IIdentificationCommand.

.

Answer 3

, Command Pattern:
- http://www.dofactory.com/Patterns/PatternCommand.aspx
- http://c2.com/cgi/wiki?CommandPattern
- http://en.wikipedia.org/wiki/Command_pattern

Also your IdentificationRequest is not like an entity class , but I would describe your Person class as an object.
Often, Invoker inside a team template sends a response to the recipient, indicating success or failure, and if successful, the response object may contain an identifier.