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    <p>Thank you all for the answers.</p> <p>jalexiou - I will look into KeyedCollection, thanks (sheesh, I really need to register so I can post comments).</p> <p>James, as I wrote, I do want to work with interfaces (if nothing else, it simplifies unit-testing). My problem is that to initialize the actual ResourceManager I would need to pass the ComponentManager, and to initialize the CM I would need to pass the RM. What you suggested is basically a two-phase initialization which I referred to as solution 2. I would prefer to avoid such two-phase initialization, but perhaps I'm being too religious here.</p> <p>Philip, I think that passing the Component to ReportNewItem would be exposing too much to the ResourceManager (since Component supports various operations that I would rather not be accesible to the ResourceManager).</p> <p>However, thinking about it again, I can take the following approach:</p> <pre><code>class ComponentManager { ... } class Component { private ComponentAccessorForResource m_accessor; private ResourceManager m_rm; Component(ResourceManager rm) { m_accessor = new ComponentAccessorForResource(this); m_rm = rm; } void DoStuff() { Item item = CreateItem(); ResourceManager.ReportNewItem(item.ID, m_accessor); } int GetMaxResource() { ... } } class ComponentAccessorForResource { private Component m_component; ComponentAccessorForResource(Component c) { m_component = c; } int GetMaxResource() { return m_component.GetMaxResource(); } } ResourceManager rm = new ResourceManager(); ComponentManager cm = new ComponentManager(rm); </code></pre> <p>This seems clean enough to me. Hope no one disagrees :)</p> <p>My original objection to passing the Component (or indeed something like the accessor I proposed here) was that I would have to re-provide them to the ResourceManager upon initialization, since the ResourceManager persistently stores the Items it has. But as it turns out I have to re-initialize it with the Items anyway, so it's not a problem.</p> <p>Thanks again for the good discussion!</p>
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    1. PODesign question - resolving circular dependency between objects
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    1. COI'm a little confused, because we switched from a ContainerManager and Container to a ComponentManager and Component... going to assume they're the same thing. There are a lot of details missing in the code you've given... the best I can say is that the ComponentManager seems to be unnecessary, or at least isn't involved in the Component/ResourceManager relationship. A component knows about its ResourceManager... okay so far, that makes sense. The ResourceManager knows about Components, since it works with those. Still okay. (more)
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    2. COIf the ComponentManager is necessary to manage components, okay, but there's no reason for it to intercede between the Component and ResourceManager. Not having the CM know about the RM solves your circular dependency issue. I'm not clear at all on what the ComponentAccessor is giving you. It seems like an unnecessary wrapper, storing exactly one component, and wrapping one function without adding any value; you might as well just expose Component.GetMaxResource. If you're not happy with my suggestion, I'd still encourage you to think some more, come up with another approach
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