mirror of
https://github.com/ShareX/ShareX.git
synced 2024-08-19 12:11:52 +12:00
247 lines
No EOL
7.7 KiB
C#
247 lines
No EOL
7.7 KiB
C#
/*
|
||
* Greenshot - a free and open source screenshot tool
|
||
* Copyright (C) 2007-2013 Thomas Braun, Jens Klingen, Robin Krom
|
||
*
|
||
* For more information see: http://getgreenshot.org/
|
||
* The Greenshot project is hosted on Sourceforge: http://sourceforge.net/projects/greenshot/
|
||
*
|
||
* This program is free software: you can redistribute it and/or modify
|
||
* it under the terms of the GNU General Public License as published by
|
||
* the Free Software Foundation, either version 1 of the License, or
|
||
* (at your option) any later version.
|
||
*
|
||
* 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.gnu.org/licenses/>.
|
||
*/
|
||
|
||
using System;
|
||
using System.Collections.Generic;
|
||
using System.Timers;
|
||
|
||
namespace GreenshotPlugin.Core
|
||
{
|
||
/// <summary>
|
||
/// Cache class
|
||
/// </summary>
|
||
/// <typeparam name="TK">Type of key</typeparam>
|
||
/// <typeparam name="TV">Type of value</typeparam>
|
||
public class Cache<TK, TV>
|
||
{
|
||
private IDictionary<TK, TV> internalCache = new Dictionary<TK, TV>();
|
||
private object lockObject = new object();
|
||
private int secondsToExpire = 10;
|
||
private CacheObjectExpired expiredCallback = null;
|
||
public delegate void CacheObjectExpired(TK key, TV cacheValue);
|
||
|
||
/// <summary>
|
||
/// Initialize the cache
|
||
/// </summary>
|
||
public Cache()
|
||
{
|
||
}
|
||
|
||
/// <summary>
|
||
/// Initialize the cache
|
||
/// </summary>
|
||
/// <param name="expiredCallback"></param>
|
||
public Cache(CacheObjectExpired expiredCallback)
|
||
: this()
|
||
{
|
||
this.expiredCallback = expiredCallback;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Initialize the cache with a expire setting
|
||
/// </summary>
|
||
/// <param name="secondsToExpire"></param>
|
||
public Cache(int secondsToExpire)
|
||
: this()
|
||
{
|
||
this.secondsToExpire = secondsToExpire;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Initialize the cache with a expire setting
|
||
/// </summary>
|
||
/// <param name="secondsToExpire"></param>
|
||
/// <param name="expiredCallback"></param>
|
||
public Cache(int secondsToExpire, CacheObjectExpired expiredCallback)
|
||
: this(expiredCallback)
|
||
{
|
||
this.secondsToExpire = secondsToExpire;
|
||
}
|
||
|
||
/// <summary>
|
||
/// Enumerable for the values in the cache
|
||
/// </summary>
|
||
public IEnumerable<TV> Elements
|
||
{
|
||
get
|
||
{
|
||
List<TV> elements = new List<TV>();
|
||
|
||
foreach (TV element in internalCache.Values)
|
||
{
|
||
elements.Add(element);
|
||
}
|
||
foreach (TV element in elements)
|
||
{
|
||
yield return element;
|
||
}
|
||
}
|
||
}
|
||
|
||
/// <summary>
|
||
/// Get the value by key from the cache
|
||
/// </summary>
|
||
/// <param name="key"></param>
|
||
/// <returns></returns>
|
||
public TV this[TK key]
|
||
{
|
||
get
|
||
{
|
||
TV result = default(TV);
|
||
lock (lockObject)
|
||
{
|
||
if (internalCache.ContainsKey(key))
|
||
{
|
||
result = internalCache[key];
|
||
}
|
||
}
|
||
return result;
|
||
}
|
||
}
|
||
|
||
/// <summary>
|
||
/// Contains
|
||
/// </summary>
|
||
/// <param name="key"></param>
|
||
/// <returns>true if the cache contains the key</returns>
|
||
public bool Contains(TK key)
|
||
{
|
||
return internalCache.ContainsKey(key);
|
||
}
|
||
|
||
/// <summary>
|
||
/// Add a value to the cache
|
||
/// </summary>
|
||
/// <param name="key"></param>
|
||
/// <param name="value"></param>
|
||
public void Add(TK key, TV value)
|
||
{
|
||
Add(key, value, null);
|
||
}
|
||
|
||
/// <summary>
|
||
/// Add a value to the cache
|
||
/// </summary>
|
||
/// <param name="key"></param>
|
||
/// <param name="value"></param>
|
||
/// <param name="secondsToExpire?">optional value for the seconds to expire</param>
|
||
public void Add(TK key, TV value, int? secondsToExpire)
|
||
{
|
||
lock (lockObject)
|
||
{
|
||
var cachedItem = new CachedItem(key, value, secondsToExpire.HasValue ? secondsToExpire.Value : this.secondsToExpire);
|
||
cachedItem.Expired += delegate(TK cacheKey, TV cacheValue)
|
||
{
|
||
if (internalCache.ContainsKey(cacheKey))
|
||
{
|
||
LOG.DebugFormat("Expiring object with Key: {0}", cacheKey);
|
||
if (expiredCallback != null)
|
||
{
|
||
expiredCallback(cacheKey, cacheValue);
|
||
}
|
||
Remove(cacheKey);
|
||
}
|
||
else
|
||
{
|
||
LOG.DebugFormat("Expired old object with Key: {0}", cacheKey);
|
||
}
|
||
};
|
||
|
||
if (internalCache.ContainsKey(key))
|
||
{
|
||
internalCache[key] = value;
|
||
LOG.DebugFormat("Updated item with Key: {0}", key);
|
||
}
|
||
else
|
||
{
|
||
internalCache.Add(key, cachedItem);
|
||
LOG.DebugFormat("Added item with Key: {0}", key);
|
||
}
|
||
}
|
||
}
|
||
|
||
/// <summary>
|
||
/// Remove item from cache
|
||
/// </summary>
|
||
/// <param name="key"></param>
|
||
public void Remove(TK key)
|
||
{
|
||
lock (lockObject)
|
||
{
|
||
if (!internalCache.ContainsKey(key))
|
||
{
|
||
throw new ApplicationException(String.Format("An object with key ‘{0}’ does not exists in cache", key));
|
||
}
|
||
internalCache.Remove(key);
|
||
LOG.DebugFormat("Removed item with Key: {0}", key);
|
||
}
|
||
}
|
||
|
||
/// <summary>
|
||
/// A cache item
|
||
/// </summary>
|
||
private class CachedItem
|
||
{
|
||
public event CacheObjectExpired Expired;
|
||
private int secondsToExpire;
|
||
private readonly Timer _timerEvent;
|
||
|
||
public CachedItem(TK key, TV item, int secondsToExpire)
|
||
{
|
||
if (key == null)
|
||
{
|
||
throw new ArgumentNullException("key is not valid");
|
||
}
|
||
Key = key;
|
||
Item = item;
|
||
this.secondsToExpire = secondsToExpire;
|
||
if (secondsToExpire > 0)
|
||
{
|
||
_timerEvent = new Timer(secondsToExpire * 1000) { AutoReset = false };
|
||
_timerEvent.Elapsed += timerEvent_Elapsed;
|
||
_timerEvent.Start();
|
||
}
|
||
}
|
||
|
||
private void ExpireNow()
|
||
{
|
||
_timerEvent.Stop();
|
||
if (secondsToExpire > 0 && Expired != null)
|
||
{
|
||
Expired(Key, Item);
|
||
}
|
||
}
|
||
|
||
private void timerEvent_Elapsed(object sender, ElapsedEventArgs e)
|
||
{
|
||
ExpireNow();
|
||
}
|
||
|
||
public TK Key { get; private set; }
|
||
public TV Item { get; private set; }
|
||
|
||
public static implicit operator TV(CachedItem a)
|
||
{
|
||
return a.Item;
|
||
}
|
||
}
|
||
}
|
||
} |