public void AddMetadata <TMetadata>(TMetadata metadata)
where TMetadata : IMetadata
{
if (metadata == null)
{
throw new ArgumentNullException(nameof(metadata));
}
if (metadata.Relation == null)
{
throw new ArgumentNullException(nameof(metadata.Relation));
}
MetadataKey key = MetadataKey.FromIdentity <TMetadata>(metadata.Relation.Identity);
if (!this.entries.TryAdd(key, metadata))
{
throw new InvalidOperationException("Metadata already added.");
}
}
