internal void ReturnExampleToCache(VowpalWabbitCachedExample <TExample> example)
{
if (this.exampleCache == null)
{
throw new ObjectDisposedException("VowpalWabbitSerializer");
}
// if we reach the cache boundary, dispose the oldest example
if (this.exampleCache.Count > this.settings.MaxExampleCacheSize)
{
var enumerator = this.exampleCache.GetEnumerator();
// this.settings.MaxExampleCacheSize is >= 1
enumerator.MoveNext();
var min = enumerator.Current;
while (enumerator.MoveNext())
{
if (min.Value.LastRecentUse > enumerator.Current.Value.LastRecentUse)
{
min = enumerator.Current;
}
}
this.exampleCache.Remove(min.Key);
min.Value.UnderlyingExample.Dispose();
}
}
/// <summary>
/// Serialize the example.
/// </summary>
/// <param name="example">The example to serialize.</param>
/// <returns>The serialized example.</returns>
/// <remarks>If TExample is annotated using the Cachable attribute, examples are returned from cache.</remarks>
public IVowpalWabbitExample Serialize(TExample example)
{
if (this.exampleCache == null)
{
return(this.serializer(example));
}
VowpalWabbitCachedExample <TExample> result;
if (this.exampleCache.TryGetValue(example, out result))
{
result.LastRecentUse = DateTime.UtcNow;
}
else
{
result = new VowpalWabbitCachedExample <TExample>(this, this.serializer(example));
this.exampleCache.Add(example, result);
}
return(result);
}