/// <summary>Evict expired entries.</summary>
private void EvictExpiredEntries()
{
long now = clock.CurrentTime();
for (int i = 0; i < EvictionLimit; i++)
{
LightWeightCache.Entry peeked = queue.Peek();
if (peeked == null || !IsExpired(peeked, now))
{
return;
}
E evicted = Evict();
Preconditions.CheckState(evicted == peeked);
}
}
public override E Get(K key)
{
E entry = base.Get(key);
if (entry != null)
{
if (accessExpirationPeriod > 0)
{
// update expiration time
LightWeightCache.Entry existing = (LightWeightCache.Entry)entry;
Preconditions.CheckState(queue.Remove(existing));
SetExpirationTime(existing, accessExpirationPeriod);
queue.Offer(existing);
}
}
return(entry);
}
public override E Put(E entry)
{
if (!(entry is LightWeightCache.Entry))
{
throw new HadoopIllegalArgumentException("!(entry instanceof Entry), entry.getClass()="
+ entry.GetType());
}
EvictExpiredEntries();
E existing = base.Put(entry);
if (existing != null)
{
queue.Remove(existing);
}
LightWeightCache.Entry e = (LightWeightCache.Entry)entry;
SetExpirationTime(e, creationExpirationPeriod);
queue.Offer(e);
EvictEntries();
return(existing);
}
internal virtual bool IsExpired(LightWeightCache.Entry e, long now)
{
return(now > e.GetExpirationTime());
}
internal virtual void SetExpirationTime(LightWeightCache.Entry e, long expirationPeriod
)
{
e.SetExpirationTime(clock.CurrentTime() + expirationPeriod);
}
