// Copyright 2009 The Noda Time Authors. All rights reserved.

// Use of this source code is governed by the Apache License 2.0,

// as found in the LICENSE.txt file.

​

using NodaTime.Annotations;

using NodaTime.TimeZones.Cldr;

using NodaTime.TimeZones.IO;

using NodaTime.Utility;

using System;

using System.Collections.Concurrent;

using System.Collections.Generic;

using System.Collections.ObjectModel;

using System.Diagnostics;

using System.IO;

using System.Linq;

using System.Threading;

​

namespace NodaTime.TimeZones

{

    /// <summary>

    /// Provides an implementation of <see cref="IDateTimeZoneSource" /> that loads data originating from the

    /// <a href="https://www.iana.org/time-zones">tz database</a> (also known as the IANA Time Zone database, or zoneinfo

    /// or Olson database).

    /// </summary>

    /// <remarks>

    /// All calls to <see cref="ForId"/> for fixed-offset IDs advertised by the source (i.e. "UTC" and "UTC+/-Offset")

    /// will return zones equal to those returned by <see cref="DateTimeZone.ForOffset"/>.

    /// </remarks>

    /// <threadsafety>This type is immutable reference type. See the thread safety section of the user guide for more information.</threadsafety>