/// <summary>
/// Removes item from cache
/// </summary>
/// <param name="key">Unique key of finding item.</param>
public void Remove(TKey key)
{
if (_Lock.TryEnterWriteLock(_DefaultLockTimeOut))
{
RemovedEntry removedItem = null;
try
{
TValue value;
if (_Cache.TryGetValue(key, out value))
{
bool removed = _Cache.Remove(key);
#if DEBUG
//ApplicationEventLog.WriteEntry("Flow", string.Format("GenericCache: removing item {0} of type {1} = removed={2}", key, typeof(TValue).Name, removed), EventLogEntryType.Information);
#endif
removedItem = new RemovedEntry()
{
Key = key, Value = value
};
}
}
finally
{
_Lock.ExitWriteLock();
}
if ((removedItem != null) && (RemovedItem != null))
{
RemovedItem(removedItem.Key, removedItem.Value);
}
}
else
{
ApplicationEventLog.WriteEntry("Flow", string.Format("GenericCache:Remove - Failed to acquire lock for key={0} ", key), EventLogEntryType.Error);
}
}
private void ClearSpaceForNewEntry()
{
if (_cache.Count >= Size)
{
LinkedListNode <string> rank = _ranking.Last;
CacheEntry entry = _cache[rank.Value];
_cache = _cache.Remove(rank.Value);
_ranking.Remove(rank);
RemovedEntry?.Invoke(this,
new CacheEntryEventArgs <TValue>(entry.Key, entry.Value));
}
}
private RemovedEntry RemoveOldestRequestedItem()
{
RemovedEntry result = null;
TValue value;
TKey key = _KeyQueue[_KeyQueueHeadIndex];
_KeyQueueHeadIndex = (_KeyQueueHeadIndex + 1) % _Capacity;
if (_Cache.TryGetValue(key, out value))
{
#if DEBUG
//ApplicationEventLog.WriteEntry("Flow", string.Format("GenericCache:Removing old item {0} of type {1}", key, typeof(TValue).Name), EventLogEntryType.Information);
#endif
_Cache.Remove(key);
result = new RemovedEntry()
{
Key = key, Value = value
};
}
return(result);
}
/// <summary>
/// Add item to cache
/// </summary>
/// <param name="key">Unique key of finding item</param>
/// <param name="item">Item to add</param>
/// <remarks>If already in cache it gets updated</remarks>
public void Add(TKey key, TValue item)
{
if (_Lock.TryEnterWriteLock(_DefaultLockTimeOut))
{
RemovedEntry removedItem = null;
try
{
TValue existingItem;
if (_Cache.TryGetValue(key, out existingItem))
{
_Cache[key] = item;
}
else if (key != null)
{
if ((_Count + 1) > _Capacity)
{
removedItem = RemoveOldestRequestedItem();
}
else
{
_Count++;
}
_Cache.Add(key, item);
_KeyQueueTailIndex = (_KeyQueueTailIndex + 1) % _Capacity;
_KeyQueue[_KeyQueueTailIndex] = key;
}
}
finally
{
_Lock.ExitWriteLock();
}
if ((removedItem != null) && (RemovedItem != null))
{
RemovedItem(removedItem.Key, removedItem.Value);
}
}
else
{
ApplicationEventLog.WriteEntry("Flow", string.Format("GenericCache:Add - Failed to acquire lock for key={0} value={1}", key, item), EventLogEntryType.Error);
}
}
/// <summary>
/// Raises the <see cref="RemovedEntry"/> event.
/// </summary>
/// <param name="e">An <see cref="DotRas.RasPhoneBookDialogEventArgs"/> containing event data.</param>
private void OnRemovedEntry(RasPhoneBookDialogEventArgs e)
{
RemovedEntry?.Invoke(this, e);
}
