Oren Eini

aka Ayende Rahien

Oren Eini

CEO of RavenDB

a NoSQL Open Source Document Database

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oren@ravendb.net

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RavenDB - High-Performance NoSQL Document Database

Mar 22 2010

I love ConcurrentDictionary!

time to read 2 min | 208 words

Not just because it is concurrent, because of this wonderful method:

public class Storage : IStorage
{
    private readonly ConcurrentDictionary<Guid, ConcurrentDictionary<int, List<object>>> values =
        new ConcurrentDictionary<Guid, ConcurrentDictionary<int, List<object>>>();

    public void Store(Guid taskId, int level, object value)
    {
        values.GetOrAdd(taskId, guid => new ConcurrentDictionary<int, List<object>>())
            .GetOrAdd(level, i => new List<object>())
            .Add(value);
    }
}

Doing this with Dictionary is always a pain, but this is an extremely natural way of doing things.

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