ThreadBlocker.cs :  » Content-Management-Systems-CMS » Kooboo » Everest » Library » Net » C# / CSharp Open Source

/*
Kooboo is a content management system based on ASP.NET MVC framework. Copyright 2009 Yardi Technology Limited.

This program is free software: you can redistribute it and/or modify it under the terms of the
GNU General Public License version 3 as published by the Free Software Foundation.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program.
If not, see http://www.kooboo.com/gpl3/.
*/

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

namespace Everest.Library.Net{
    public class ThreadBlocker
    {
        /// <summary>
        /// ThreadBlocker Constructor.
        /// </summary>
        public ThreadBlocker()
            : this(null)
        {
        }

        /// <summary>
        /// ThreadBlocker Constructor.
        /// </summary>
        /// <param name="releaseCondition">
        /// Return boolean value 'true' to release block.
        /// </param>
        public ThreadBlocker(Func<bool> releaseCondition)
        {
            this.ReleaseCondition = releaseCondition;
        }

        // release codition function.
        private Func<bool> ReleaseCondition;
        // released flag.
        private bool isReleased;
        // default inquire timespan, 100 millisecond.
        private const int _inquireTime = 100;
        // default to one minute.
        private int _timeOut = 60 * 1000;

        /// <summary>
        /// Wait timeout(millisecond).
        /// </summary>
        public int Timeout
        {
            get { return _timeOut; }
            set { _timeOut = value; }
        }

        /// <summary>
        /// Wait core.
        /// </summary>
        public void Wait()
        {
            var totalTime = 0;
            isReleased = false;
            while ((isReleased == false) && (totalTime < this.Timeout) &&
                   ((this.ReleaseCondition == null) || (!this.ReleaseCondition())))
            {
                totalTime += _inquireTime;
                Thread.Sleep(_inquireTime);
            }
        }

        /// <summary>
        /// Release blocker.
        /// </summary>
        public void Release()
        {
            isReleased = true;
        }

        /// <summary>
        /// Block current thread.
        /// </summary>
        /// <param name="timeout">Wait timeout(millisecond).</param>
        public static ThreadBlocker Wait(int timeout)
        {
            return Wait(timeout, null);
        }

        /// <summary>
        /// Block current thread.
        /// </summary>
        /// <param name="timeout">Wait timeout(millisecond).</param>
        /// <param name="releaseCondition">
        /// Return boolean value 'true' to release block.
        /// </param>
        public static ThreadBlocker Wait(int timeout, Func<bool> releaseCondition)
        {
            var blocker = new ThreadBlocker(releaseCondition);
            blocker.Timeout = timeout;
            blocker.Wait();
            return blocker;
        }
    }
}