[C#実践開発手法]プロファイリングデコレーターより

CompleateProfilingUserService.cs

using ProfilingInterfaces;
using ServiceInterfaces;

namespace ServiceImplementations
{
    public class CompleateProfilingUserService : IUserService
    {
        private readonly IUserService _service;
        private readonly ITimeKeeper _timeKeeper;
        public CompleateProfilingUserService(IUserService service, ITimeKeeper timeKeeper)
        {
            this._service = service;
            this._timeKeeper = timeKeeper;
        }

        public string GetName()
        {
            _timeKeeper.Start();
            var result = _service.GetName();
            _timeKeeper.Stop();
            return result;
        }
    }
}

ITimeKeeper.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ProfilingInterfaces
{
    public interface ITimeKeeper
    {
        void Start();
        long Stop();
    }
}

IUserService.cs

namespace ServiceInterfaces
{
    public interface IUserService
    {
        string GetName();
    }
}

Program.cs

using System;
using System.Diagnostics;
using ProfilingImplementations;
using ProfilingInterfaces;
using ServiceImplementations;

namespace Profiling.UI
{
    class Program
    {
        static void Main(string[] args)
        {
            var nomalController = new UserController(new UserService());
            nomalController.Display();

            var profilingController = new UserController(
                new CompleateProfilingUserService(
                    new UserService(), 
                    new TimeKeeper(
                        new StopwatchAdapter(
                            new Stopwatch()
                            )
                        )
                    )
                );
            profilingController.Display();
            Console.ReadKey();
        }
    }
}

StopwatchAdapter.cs

using System.Diagnostics;
using ProfilingInterfaces;

namespace ProfilingImplementations
{
    public class StopwatchAdapter : ITimeKeeper
    {
        private readonly Stopwatch _stopwatch;
        public StopwatchAdapter(Stopwatch stopwatch)
        {
            this._stopwatch = stopwatch;
        }

        public void Start()
        {
            _stopwatch.Start();
        }

        public long Stop()
        {
            _stopwatch.Stop();
            var time = _stopwatch.ElapsedMilliseconds;
            _stopwatch.Reset();
            return time;
        }
    }
}

TimeKeeper.cs

using System;
using ProfilingInterfaces;

namespace ProfilingImplementations
{
    public class TimeKeeper : ITimeKeeper
    {
        private readonly ITimeKeeper _timekeeper;
        public TimeKeeper(ITimeKeeper timekeeper)
        {
            this._timekeeper = timekeeper;
        }

        public void Start() 
        {
            Console.WriteLine("Process Start...");
            _timekeeper.Start();
        }

        public long Stop()
        {
            var time = _timekeeper.Stop();
            Console.WriteLine("\t実行時間 {0} seconds", TimeSpan.FromMilliseconds(time).TotalSeconds);
            return time;
        }
    }
}

UserController.cs

using System;
using ServiceInterfaces;

namespace Profiling.UI
{
    internal class UserController
    {
        private readonly IUserService _service;
        public UserController(IUserService service)
        {
            this._service = service;
        }

        internal void Display()
        {
            var name = _service.GetName();

            Console.WriteLine("Hi {0} !", name);
        }
    }
}

UserService.cs

using ServiceInterfaces;

namespace ServiceImplementations
{
    public class UserService : IUserService
    {
        public string GetName()
        {
            System.Threading.Thread.Sleep(3000);
            return "BoB";
        }
    }
}

参考にさせていただいたコードの～Componentという記述で混乱したので自分なりに読み替えてみたけど、余計わかりにくくなったかも。。。