using System;
using System.Collections.Generic;
namespace DoFactory.GangOfFour.Mediator.RealWorld
{
/// <summary>
/// MainApp startup class for Real-World
/// Mediator Design Pattern.
/// </summary>
class MainApp
{
/// <summary>
/// Entry point into console application.
/// </summary>
static void Main()
{
// Create chatroom
Chatroom chatroom = new Chatroom();
// Create participants and register them
Participant George = new Beatle("George");
Participant Paul = new Beatle("Paul");
Participant Ringo = new Beatle("Ringo");
Participant John = new Beatle("John");
Participant Yoko = new NonBeatle("Yoko");
chatroom.Register(George);
chatroom.Register(Paul);
chatroom.Register(Ringo);
chatroom.Register(John);
chatroom.Register(Yoko);
// Chatting participants
Yoko.Send("John", "Hi John!");
Paul.Send("Ringo", "All you need is love");
Ringo.Send("George", "My sweet Lord");
Paul.Send("John", "Can't buy me love");
John.Send("Yoko", "My sweet love");
// Wait for user
Console.ReadKey();
}
}
/// <summary>
/// The 'Mediator' abstract class
/// </summary>
abstract class AbstractChatroom
{
public abstract void Register(Participant participant);
public abstract void Send(
string from, string to, string message);
}
/// <summary>
/// The 'ConcreteMediator' class
/// </summary>
class Chatroom : AbstractChatroom
{
private Dictionary<string,Participant> _participants =
new Dictionary<string,Participant>();
public override void Register(Participant participant)
{
if (!_participants.ContainsValue(participant))
{
_participants[participant.Name] = participant;
}
participant.Chatroom = this;
}
public override void Send(
string from, string to, string message)
{
Participant participant = _participants[to];
if (participant != null)
{
participant.Receive(from, message);
}
}
}
/// <summary>
/// The 'AbstractColleague' class
/// </summary>
class Participant
{
private Chatroom _chatroom;
private string _name;
// Constructor
public Participant(string name)
{
this._name = name;
}
// Gets participant name
public string Name
{
get { return _name; }
}
// Gets chatroom
public Chatroom Chatroom
{
set { _chatroom = value; }
get { return _chatroom; }
}
// Sends message to given participant
public void Send(string to, string message)
{
_chatroom.Send(_name, to, message);
}
// Receives message from given participant
public virtual void Receive(
string from, string message)
{
Console.WriteLine("{0} to {1}: '{2}'",
from, Name, message);
}
}
/// <summary>
/// A 'ConcreteColleague' class
/// </summary>
class Beatle : Participant
{
// Constructor
public Beatle(string name)
: base(name)
{
}
public override void Receive(string from, string message)
{
Console.Write("To a Beatle: ");
base.Receive(from, message);
}
}
/// <summary>
/// A 'ConcreteColleague' class
/// </summary>
class NonBeatle : Participant
{
// Constructor
public NonBeatle(string name)
: base(name)
{
}
public override void Receive(string from, string message)
{
Console.Write("To a non-Beatle: ");
base.Receive(from, message);
}
}
}