private void RemoveEntry(CacheEntry entry)
{
_entryLock.EnterWriteLock();
try
{
// Only remove it if someone hasn't modified it since our lookup
CacheEntry currentEntry;
if (_entries.TryGetValue(entry.Key, out currentEntry)
&& object.ReferenceEquals(currentEntry, entry))
{
_entries.Remove(entry.Key);
}
}
finally
{
_entryLock.ExitWriteLock();
}
entry.InvokeEvictionCallbacks();
}
public object Set(object key, object value, MemoryCacheEntryOptions cacheEntryOptions)
{
if (key == null)
{
throw new ArgumentNullException(nameof(key));
}
CheckDisposed();
CacheEntry priorEntry = null;
var utcNow = _clock.UtcNow;
DateTimeOffset? absoluteExpiration = null;
if (cacheEntryOptions.AbsoluteExpirationRelativeToNow.HasValue)
{
absoluteExpiration = utcNow + cacheEntryOptions.AbsoluteExpirationRelativeToNow;
}
else if (cacheEntryOptions.AbsoluteExpiration.HasValue)
{
if (cacheEntryOptions.AbsoluteExpiration <= utcNow)
{
throw new ArgumentOutOfRangeException(
nameof(MemoryCacheEntryOptions.AbsoluteExpiration),
cacheEntryOptions.AbsoluteExpiration.Value,
"The absolute expiration value must be in the future.");
}
absoluteExpiration = cacheEntryOptions.AbsoluteExpiration;
}
var entry = new CacheEntry(
key,
value,
utcNow,
absoluteExpiration,
cacheEntryOptions,
_entryExpirationNotification);
var link = EntryLinkHelpers.ContextLink;
if (link != null)
{
// Copy expiration tokens and AbsoluteExpiration to the link.
// We do this regardless of it gets cached because the tokens are associated with the value we'll return.
if (entry.Options.ExpirationTokens != null)
{
link.AddExpirationTokens(entry.Options.ExpirationTokens);
}
if (absoluteExpiration.HasValue)
{
link.SetAbsoluteExpiration(absoluteExpiration.Value);
}
}
bool added = false;
_entryLock.EnterWriteLock();
try
{
if (_entries.TryGetValue(key, out priorEntry))
{
_entries.Remove(key);
priorEntry.SetExpired(EvictionReason.Replaced);
}
if (!entry.CheckExpired(utcNow))
{
_entries[key] = entry;
entry.AttachTokens();
added = true;
}
}
finally
{
_entryLock.ExitWriteLock();
}
if (priorEntry != null)
{
priorEntry.InvokeEvictionCallbacks();
}
if (!added)
{
entry.InvokeEvictionCallbacks();
}
StartScanForExpiredItems();
return value;
}
private void EntryExpired(CacheEntry entry)
{
// TODO: For efficiency consider processing these expirations in batches.
RemoveEntry(entry);
StartScanForExpiredItems();
}
public object Set([NotNull] string key, IEntryLink link, object state, [NotNull] Func<ICacheSetContext, object> create)
{
CheckDisposed();
CacheEntry priorEntry = null;
var now = _clock.UtcNow;
var context = new CacheSetContext(key) { State = state, CreationTime = now };
object value = create(context);
var entry = new CacheEntry(context, value, _entryExpirationNotification);
bool added = false;
if (link != null)
{
// Copy triggers and AbsoluteExpiration to the link.
// We do this regardless of it gets cached because the triggers are associated with the value we'll return.
if (entry.Context.Triggers != null)
{
link.AddExpirationTriggers(entry.Context.Triggers);
}
if (entry.Context.AbsoluteExpiration.HasValue)
{
link.SetAbsoluteExpiration(entry.Context.AbsoluteExpiration.Value);
}
}
_entryLock.EnterWriteLock();
try
{
if (_entries.TryGetValue(key, out priorEntry))
{
_entries.Remove(key);
priorEntry.SetExpired(EvictionReason.Replaced);
}
if (!entry.CheckExpired(now))
{
_entries[key] = entry;
entry.AttachTriggers();
added = true;
}
}
finally
{
_entryLock.ExitWriteLock();
}
if (priorEntry != null)
{
priorEntry.InvokeEvictionCallbacks();
}
if (!added)
{
entry.InvokeEvictionCallbacks();
}
StartScanForExpiredItems();
return value;
}
public object Set(object key, object value, MemoryCacheEntryOptions cacheEntryOptions)
{
if (key == null)
{
throw new ArgumentNullException(nameof(key));
}
CheckDisposed();
CacheEntry priorEntry = null;
var utcNow = _clock.UtcNow;
DateTimeOffset?absoluteExpiration = null;
if (cacheEntryOptions.AbsoluteExpirationRelativeToNow.HasValue)
{
absoluteExpiration = utcNow + cacheEntryOptions.AbsoluteExpirationRelativeToNow;
}
else if (cacheEntryOptions.AbsoluteExpiration.HasValue)
{
if (cacheEntryOptions.AbsoluteExpiration <= utcNow)
{
throw new ArgumentOutOfRangeException(
nameof(MemoryCacheEntryOptions.AbsoluteExpiration),
cacheEntryOptions.AbsoluteExpiration.Value,
"The absolute expiration value must be in the future.");
}
absoluteExpiration = cacheEntryOptions.AbsoluteExpiration;
}
var entry = new CacheEntry(
key,
value,
utcNow,
absoluteExpiration,
cacheEntryOptions,
_entryExpirationNotification);
var link = EntryLinkHelpers.ContextLink;
if (link != null)
{
// Copy expiration tokens and AbsoluteExpiration to the link.
// We do this regardless of it gets cached because the tokens are associated with the value we'll return.
if (entry.Options.ExpirationTokens != null)
{
link.AddExpirationTokens(entry.Options.ExpirationTokens);
}
if (absoluteExpiration.HasValue)
{
link.SetAbsoluteExpiration(absoluteExpiration.Value);
}
}
bool added = false;
_entryLock.EnterWriteLock();
try
{
if (_entries.TryGetValue(key, out priorEntry))
{
_entries.Remove(key);
priorEntry.SetExpired(EvictionReason.Replaced);
}
if (!entry.CheckExpired(utcNow))
{
_entries[key] = entry;
entry.AttachTokens();
added = true;
}
}
finally
{
_entryLock.ExitWriteLock();
}
if (priorEntry != null)
{
priorEntry.InvokeEvictionCallbacks();
}
if (!added)
{
entry.InvokeEvictionCallbacks();
}
StartScanForExpiredItems();
return(value);
}
private void EntryExpired(CacheEntry entry)
{
// TODO: For efficiency consider processing these expirations in batches.
RemoveEntry(entry);
StartScanForExpiredItems();
}
public bool TryGetValue(object key, out object value)
{
if (key == null)
{
throw new ArgumentNullException(nameof(key));
}
value = null;
CacheEntry expiredEntry = null;
bool found = false;
CheckDisposed();
_entryLock.EnterReadLock();
try
{
CacheEntry entry;
if (_entries.TryGetValue(key, out entry))
{
// Check if expired due to expiration tokens, timers, etc. and if so, remove it.
if (entry.CheckExpired(_clock.UtcNow))
{
expiredEntry = entry;
}
else
{
// Refresh sliding expiration, etc.
entry.LastAccessed = _clock.UtcNow;
value = entry.Value;
found = true;
var link = EntryLinkHelpers.ContextLink;
if (link != null)
{
// Copy expiration tokens and AbsoluteExpiration to the link
if (entry.Options.ExpirationTokens != null)
{
link.AddExpirationTokens(entry.Options.ExpirationTokens);
}
if (entry.Options.AbsoluteExpiration.HasValue)
{
link.SetAbsoluteExpiration(entry.Options.AbsoluteExpiration.Value);
}
}
}
}
}
finally
{
_entryLock.ExitReadLock();
}
if (expiredEntry != null)
{
// TODO: For efficiency queue this up for batch removal
RemoveEntry(expiredEntry);
}
StartScanForExpiredItems();
return(found);
}
private static void InvokeCallbacks(CacheEntry entry)
{
var callbackRegistrations = entry.PostEvictionCallbacks;
entry.PostEvictionCallbacks = null;
if (callbackRegistrations == null)
{
return;
}
for (int i = 0; i < callbackRegistrations.Count; i++)
{
var registration = callbackRegistrations[i];
try
{
registration.EvictionCallback?.Invoke(entry.Key, entry.Value, entry.EvictionReason, registration.State);
}
catch (Exception)
{
// This will be invoked on a background thread, don't let it throw.
// TODO: LOG
}
}
}