protected override void ExitLock()
{
if (CacheLock.IsWriteLockHeld)
{
CacheLock.ExitWriteLock();
}
}
/// <summary>
/// Clear all cached values
/// </summary>
public void Clear()
{
CacheLock.EnterWriteLock();
try {
Cache.Clear();
} finally {
CacheLock.ExitWriteLock();
}
}
/// <summary>
/// Remove cached value
/// </summary>
/// <param name="key">Cache key</param>
public void Remove(TKey key)
{
RevokeExpires();
CacheLock.EnterWriteLock();
try {
Cache.Remove(key);
} finally {
CacheLock.ExitWriteLock();
}
}
protected override void ExitLock()
{
if (CacheLock.IsWriteLockHeld)
{
CacheLock.ExitWriteLock();
}
if (CacheLock.IsUpgradeableReadLockHeld)
{
CacheLock.ExitUpgradeableReadLock();
}
}
/// <summary>
/// Put value to cache
/// </summary>
/// <param name="key">Cache key</param>
/// <param name="value">Cache value</param>
/// <param name="keepTime">Keep time</param>
public void Put(TKey key, TValue value, TimeSpan keepTime)
{
RevokeExpires();
if (keepTime == TimeSpan.Zero)
{
return;
}
var now = DateTime.UtcNow;
CacheLock.EnterWriteLock();
try {
Cache[key] = Pair.Create(value, now + keepTime);
} finally {
CacheLock.ExitWriteLock();
}
}
/// <summary>
/// Revoke expired values if the check interval has elapsed
/// </summary>
protected void RevokeExpires()
{
var now = DateTime.UtcNow;
if ((now - LastRevokeExpires) < RevokeExpiresInterval)
{
return;
}
CacheLock.EnterWriteLock();
try {
if ((now - LastRevokeExpires) < RevokeExpiresInterval)
{
return; // double check
}
LastRevokeExpires = now;
var expireKeys = Cache.Where(c => c.Value.Second < now).Select(c => c.Key).ToList();
foreach (var key in expireKeys)
{
Cache.Remove(key);
}
} finally {
CacheLock.ExitWriteLock();
}
}