Zajęcia, rok akademicki 2011/2012, semestr 2

Wykład skierowany jest do przyszłych architektów i projektantów systemów informatycznych oraz do wszystkich programistów zainteresowanych udoskonaleniem swojego warsztatu. Celem wykładu jest zapoznanie studentów z kanonem współczesnych narzędzi w zakresie projektowania obiektowego oprogramowania.

Wymagania

Organizacja pracy

Egzamin

Ranking

Wykłady

Implementacje

EventAggregator

namespace Uwr.OOP.BehavioralPatterns.EventAggregator
{
    public interface ISubscriber<T>
    {
        void Handle( T Notification );
    }

    public interface IEventAggregator
    {
        void AddSubscriber<T>( ISubscriber<T> Subscriber );
        void RemoveSubscriber<T>( ISubscriber<T> Subscriber );
        void Publish<T>( T Event );
    }

    public class EventAggregator : IEventAggregator
    {
        Dictionary<Type, List<object>> _subscribers = new Dictionary<Type, List<object>>();

        #region IEventAggregator Members

        public void AddSubscriber<T>( ISubscriber<T> Subscriber )
        {
            if ( !_subscribers.ContainsKey( typeof( T ) ) ) 
                _subscribers.Add( typeof(T), new List<object>() );

            _subscribers[typeof( T )].Add( Subscriber );
        }

        public void RemoveSubscriber<T>( ISubscriber<T> Subscriber )
        {
            if ( _subscribers.ContainsKey( typeof( T ) ) )
                _subscribers[typeof( T )].Remove( Subscriber );
        }

        public void Publish<T>( T Event )
        {
            if ( _subscribers.ContainsKey( typeof( T ) ) )
                foreach ( ISubscriber<T> subscriber in _subscribers[typeof( T )].OfType<ISubscriber<T>>() )
                    subscriber.Handle( Event );
        }

        #endregion
    }
}

Memento

namespace UWr.OOP.BehavioralPatterns2.Memento.MementoStructural
{
    public class Originator    
    {
        public Originator()
        {
        }

        public string State { get; set; }

        public Memento CreateMemento()
        {
            Memento m = new Memento();
            m.SetState( this.State );
            return m;
        }

        public void RestoreMemento( Memento m )
        {
            this.State = m.GetState();
        }

    }

    public class Memento
    {
        public string StateBackup { get; set;}

        public Memento()
        {

        }

        public string GetState()
        {
            return this.StateBackup;
        }

        public void SetState( string StateToSet )
        {
            this.StateBackup = StateToSet;
        }
    }

    [TestFixture]
    public class Caretaker
    {
        [Test]
        public void TestMemento()
        {
            Originator o = new Originator();

            o.State = "foo";
            Assert.That( o.State == "foo" );

            Memento m1 = o.CreateMemento();

            o.State = "bar";
            Assert.That( o.State == "bar" );

            Memento m2 = o.CreateMemento();

            o.State = "qux";
            Assert.That( o.State == "qux" );

            o.RestoreMemento( m2 );
            Assert.That( o.State == "bar" );

            o.RestoreMemento( m1 );
            Assert.That( o.State == "foo" );
        }
    }
}

namespace UWr.OOP.BehavioralPatterns2.Memento.UndoRedo
{
    public class Originator
    {
        Stack undoStates = new Stack();
        Stack redoStates = new Stack();

        public Originator()
        {
        }

        private string _state;
        public string State 
        {
            get { return _state; }
            set 
            {
                undoStates.Push( CreateMemento( this.State, value ) );
                redoStates.Clear();

                _state = value;
            }
        }

        public void Undo()
        {
            if ( undoStates.Count > 1 )
            {
                Memento state = undoStates.Pop();
                redoStates.Push( state );

                this._state = state.From;
            }
        }

        public void Redo()
        {
            if ( redoStates.Count > 0 )
            {
                Memento state = redoStates.Pop();
                undoStates.Push( state );

                this._state = state.To;
            }
        }

        public Memento CreateMemento( string From, string To )
        {
            Memento m = new Memento();
            m.SetState( From, To );
            return m;
        }

    }

    public class Memento
    {
        public string From { get; set; }
        public string To   { get; set; }

        public Memento()
        {

        }

        public void SetState( string From, string To )
        {
            this.From = From;
            this.To = To;
        }
    }

    [TestFixture]
    public class Client
    {
        [Test]
        public void TestMemento()
        {
            Originator o = new Originator();

            o.State = "foo";
            Assert.That( o.State == "foo" );

            o.State = "bar";
            Assert.That( o.State == "bar" );

            o.State = "qux";
            Assert.That( o.State == "qux" );

            o.Undo();
            Assert.That( o.State == "bar" );
            o.Undo();
            Assert.That( o.State == "foo" );
            o.Undo();
            Assert.That( o.State == "foo" ); // nie za daleko
            o.Redo();
            Assert.That( o.State == "bar" );
            o.Redo();
            Assert.That( o.State == "qux" );
            o.Redo();
            Assert.That( o.State == "qux" ); // nie za daleko

            // undo + zmiana stanu
            o.Undo();
            Assert.That( o.State == "bar" );
            o.State = "baz";
            o.Redo();
            Assert.That( o.State == "baz" );
            o.Undo();
            Assert.That( o.State == "bar" );
        }
    }
}