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    <p>With the risk of oversimplifying things: why not make the fact whether a <code>Product</code> is fresh something a product "knows"? A <code>Store</code> (or any other kind of related object) should not have to know how to determine whether a product is still fresh; in other words, the fact that something like <code>freshSpecification</code> or <code>productTypeValidityTerm</code> even exist should not be known to <code>Store</code>, it should simply check <code>Product.IsFresh</code> (or possibly some other name that aligns better with the real world, like <code>ShouldbeSoldBy</code>, <code>ExpiresAfter</code>, etc.). The product could then be aware how to actually retrieve the <code>protductTypeValidityTerm</code> by injecting the repository dependency.</p> <p>It sounds to me like you are externalizing behavior which should be intrinsic to your domain aggregates/entities, eventually leading (again) to an anemic domain model. </p> <p>Of course, in a more complicated scenario, where freshness depends on context (e.g., what's acceptable in a budget store is not deemed worthy for sale at a premium outlet) you'd need to externalize the entire behavior, both from product and from store, and create a different type altogether to model this particular behavior.</p> <p><strong>Added after comment</strong></p> <p>Something along these lines for the simple scenario I mentioned: make the <code>FreshSpec</code> part of the Product aggregate, which allows the <code>ProductRepository</code> (constructor-injected here) to (lazy) load it when needed.</p> <pre><code>public class Product { public ProductType ProductType { get; set; } public DateTime ProducedOn { get; set; } private FreshSpecification FreshSpecification { get; set; } public Product(IProductRepository productRepository) { } public bool IsFresh() { return FreshSpecification .IsSatisfiedBy(ProductType, ProducedOn); } } </code></pre> <p>The store doesn't know about these internals: all it cares about is whether or not the product is fresh:</p> <pre><code>public class Store { private List&lt;Product&gt; Products = new List&lt;Product&gt;(); public void AddProduct(Product product) { if (product.IsFresh()) { Products.Add(product); } } } </code></pre>
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    1. COI thought about this too - that i'm just modeling this wrong. I would be happy to accept your answer if you could rewrite my pseudo-code to reflect your idea.
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    2. CO@tijmenvdk So - it's fine to inject product repository into product object, right? Somewhere read that it should be avoided (on the other hand, it kind a seems completely reasonable).
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    3. COSo - basically, entities could be compared a bit with those well known good old `ProductManager`s but with all technical side stripped off and more thoroughly and carefully modeled. Is that right?
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