Manage software dependencies with io c and aop

1. Manage software dependencies with IoC and AOP Stefano Leli 14° Workshop DotNetMarche Friday 16 th April 2010 @sleli [email_address]

4. Dependencies public RequestService() { ClassB b = new ClassB() b.DoService(); } dependent +DoService() ClassA +RequestService() ClassB

8. Copier Example Copier + PerformCopy() Keyboard + ReadFromKB(c : char ) Video + WriteToVideo () : char

12. Copier Example <<create>> <<create>> Concrete class should depend on abstraction Robert Martin IWriter IReader Copier + PerformCopy() Keyboard + Read(c : char ) Video + Write () : char

16. <<create>> Using a Factory <<create>> Copier + Copier(r : IReader, w : IWriter) + PerformCopy() IWriter IReader Keyboard + Read(c : char ) Video + Write () : char ReaderFactory + GetInstance() : IReader WriterFactory + GetInstance() : IWriter

19. Service Locator << create >> <<create>> Copier + PerformCopy() ServiceLocator +Lookup() : Object +RegisterService(o : Object) _instance : ServiceLocator … IWriter IReader Keyboard + Read(c : char ) Video + Write () : char

20. Service Locator << create >> <<create>> Copier + PerformCopy() ServiceLocator +Lookup() : Object +RegisterService(o : Object) _instance : ServiceLocator … IWriter IReader Keyboard + Read(c : char ) Video + Write () : char

21. Service Locator class ServiceLocator { /* Singleton instance */ private static ServiceLocator _instance; public static void Load(ServiceLocator arg) { _instance = arg; } /* Storing and Retrieve services */ private Dictionary<string, Object> _services = new Dictionary<string, Object>(); public Object RegisterService(String key) { return _instance._services[key]; } public static void Lookup(String key, Object service) { _services.Add(key, service); } }

27. IoC Container Copier + Copier(r : IReader, w : IWriter) + PerformCopy() IWriter IReader Keyboard + Read(c : char ) Video + Write () : char

28. << create >> <<create>> IoC Container <<create>> Copier + Copier(r : IReader, w : IWriter) + PerformCopy() XML Config IWriter IReader Keyboard + Read(c : char ) Video + Write () : char IoCContainer …

35. Separation of Concern Searching Booking Payment

38. Crosscutting Concern Booking Payment Searching Security Logging AOP Booking Security Logging Payment Security Logging Searching Security Logging OOP Crosscutting Concerns Searching Booking Payment

39. How it works… Object_B Object_A Object Oriented Flow

40. How it works… Aspect Object_B Object_A advice Object Oriented Flow Aspect Oriented Flow pointcut = method_B Target Object = Object_B jointpoint = method invocation

48. Questions?