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    <p>I agree with your concerns. It's a code smell to take dependencies for the sole purpose of passing them on to other dependencies.</p> <p>Depending on the exact interaction between those dependencies, you have a couple of options:</p> <p><strong>If only one instance of the dependency is needed</strong></p> <p>If your Controller only needs a single instance of a dependency, then just take a dependency on that instead.</p> <p>(apologies for the c# code)</p> <p><strong>Don't</strong> do this:</p> <pre><code>public class MyController { public MyController(IDb db) { var dep = new MyDependency(db); // Use dep or save it for later } } </code></pre> <p>Instead, you can do this:</p> <pre><code>public class MyController { public MyController(MyDependency dep) { // Use dep or save it for later } } </code></pre> <p>You may want to consider <code>MyDependency</code> behind an interface itself. See also <a href="http://blog.ploeh.dk/2010/02/02/RefactoringToAggregateServices.aspx" rel="nofollow noreferrer">Refactoring to Aggregate Services</a>.</p> <p><strong>If you need to create multiple instances during the Controller's lifetime</strong></p> <p>Sometimes, however, you need to create multiple instances dynamically. This is often the case when you need a value that's only available at run-time before you can fully populate a dependency.</p> <p>In this case, an <a href="http://en.wikipedia.org/wiki/Abstract_factory_pattern" rel="nofollow noreferrer">Abstract Factory</a> is an <a href="https://stackoverflow.com/questions/1926826/cant-combine-factory-di/1927167#1927167">excellent and universal solution</a>.</p>
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    1. POHow to avoid injecting dependencies into an object so that it can pass them on?
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    1. USCommunity
    1. USMark Seemann
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    1. POHow to avoid injecting dependencies into an object so that it can pass them on?
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    1. COI don't fully understand what you propose I should do with your first option. Are you bundling the dependencies together and passing them as one?
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      1. USPeter Horne
    2. COThat's one option. The main point, however, is that the consumer shouldn't create the dependency at all, but rather request it by requiring it as a constructor parameter.
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      1. USMark Seemann
    3. COIsn't bundling the dependencies together and passing them to the controller pretty much the same as passing them all individually? It is a different way of doing it, but you are still passing dependencies to the controller that it doesn't use. I think I might have misunderstood what you meant though!
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