Using the Specification Pattern

Posted by Kane on Stack Overflow See other posts from Stack Overflow or by Kane
Published on 2010-03-24T09:15:22Z Indexed on 2010/03/24 12:43 UTC
Read the original article Hit count: 578

Filed under:

c#

|

specification-pattern

Like any design pattern the Specification Pattern is a great concept but susceptible to overuse by an eager architect/developer.

I am about to commence development on a new application (.NET & C#) and really like the concept of the Specification Pattern and am keen to make full use of it. However before I go in all guns blazing I would be really interested in knowing if anyone could share the pain points that experienced when use the Specification Pattern in developing an application.

Ideally I'm looking to see if others have had issues in

Writing unit tests against the specification pattern
Deciding which layer the specifications should live in (Repository, Service, Domain, etc)
Using it everywhere when a simple if statement would have done the job
etc?

Thanks in advance

© Stack Overflow or respective owner

Related posts about c#

.NET WebRequest.PreAuthenticate not quite what it sounds like

as seen on West-Wind - Search for 'West-Wind'
I’ve run into the problem a few times now: How to pre-authenticate .NET WebRequest calls doing an HTTP call to the server – essentially send authentication credentials on the very first request instead of waiting for a server challenge first? At first glance this sound like it should be easy:… >>> More
HttpWebRequest and Ignoring SSL Certificate Errors

as seen on West-Wind - Search for 'West-Wind'
Man I can't believe this. I'm still mucking around with OFX servers and it drives me absolutely crazy how some these servers are just so unbelievably misconfigured. I've recently hit three different 3 major brokerages which fail HTTP validation with bad or corrupt certificates at least according to… >>> More
Dynamic Type to do away with Reflection

as seen on West-Wind - Search for 'West-Wind'
The dynamic type in C# 4.0 is a welcome addition to the language. One thing I’ve been doing a lot with it is to remove explicit Reflection code that’s often necessary when you ‘dynamically’ need to walk and object hierarchy. In the past I’ve had a number of ReflectionUtils that used string based expressions… >>> More
The dynamic Type in C# Simplifies COM Member Access from Visual FoxPro

as seen on West-Wind - Search for 'West-Wind'
I’ve written quite a bit about Visual FoxPro interoperating with .NET in the past both for ASP.NET interacting with Visual FoxPro COM objects as well as Visual FoxPro calling into .NET code via COM Interop. COM Interop with Visual FoxPro has a number of problems but one of them at least got a lot… >>> More
Finding a Relative Path in .NET

as seen on West-Wind - Search for 'West-Wind'
Here’s a nice and simple path utility that I’ve needed in a number of applications: I need to find a relative path based on a base path. So if I’m working in a folder called c:\temp\templates\ and I want to find a relative path for c:\temp\templates\subdir\test.txt I want to receive back subdir\test… >>> More

Related posts about specification-pattern

Using the Specification Pattern

as seen on Stack Overflow - Search for 'Stack Overflow'
Like any design pattern the Specification Pattern is a great concept but susceptible to overuse by an eager architect/developer. I am about to commence development on a new application (.NET & C#) and really like the concept of the Specification Pattern and am keen to make full use of it. However… >>> More
Specification Pattern and Boolean Operator Precedence

as seen on Stack Overflow - Search for 'Stack Overflow'
In our project, we have implemented the Specification Pattern with boolean operators (see DDD p 274), like so: public abstract class Rule { public Rule and(Rule rule) { return new AndRule(this, rule); } public Rule or(Rule rule) { return new OrRule(this, rule); … >>> More
Specification Pattern vs Spec in BDD

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to explore Behavior Driven Design and Domain Driven Design. I'm getting that written specifications drive the tests in BDD, but also that business logic can be encapsulated using the specification pattern for re-use in domain objects and repositories, etc. Are these basically the same… >>> More
good way to implement NotSpecification: isSpecialCaseOf?

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm implementing the specification pattern. The NotSpecification seems simple at first: NotSpecification.IsSpecialCaseOf(otherSpecification) return !this.specification.isSpecialCaseOf(otherSpecification) But it doesn't work for all Specifications: Not(LesserThan(5)).IsSpecialCaseOf(GreaterThan(4)) This… >>> More
Domain Validation in a CQRS architecture

as seen on Stack Overflow - Search for 'Stack Overflow'
Basically I want to know if there is a better way to validate my domain entities. This is how I am planning to do it but I would like your opinion The first approach I considered was: class Customer : EntityBase<Customer> { public void ChangeEmail(string email) { if(string.IsNullOrWhitespace(email))… >>> More