public async Task <TItem> GetOrCreate(MultiKey key, Func <BitArray, int, TItem> createItem)
{
var hash = key.GetHashCode();
if (!_cache.TryGetValue(hash, out TItem cacheEntry))
{
var itemLock = _locks.GetOrAdd(hash, k => new SemaphoreSlim(1, 1));
await itemLock.WaitAsync();
try
{
if (!_cache.TryGetValue(hash, out cacheEntry))
{
cacheEntry = createItem(key.Key1, key.Key2);
_cache.Set(hash, cacheEntry, entryOptions);
}
}
finally
{
itemLock.Release();
}
}
return(cacheEntry);
}
public bool Equals(MultiKey other)
{
return(GetHashCode().Equals(other.GetHashCode()));
}