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copied!<p>Depending on what you mean by your question, here's what Guice (a DI framework for Java) uses:</p> <p>If you simply want a distinct object every time you have an injection request for <code>Foo</code>, then when wiring up your application don't bind <code>Foo.class</code> to a particular instance of <code>Foo</code>, but instead bind a <code>Provider<Foo></code>, which is an object that creates a <code>Foo</code> on demand. Then, every place where <code>Foo</code> is injected will get a new instance. If you just bind <code>Foo</code> to a class instead of a <code>Foo</code> instance (say, <code>Foo</code> is an interface, and you bound it to <code>RealFoo.class</code> which is a class that implements <code>Foo</code>), you also get the same effect - a new instance is created every time. (This is the default, "unscoped" behavior. The behavior of Guice scopes is beyond the scope of this comment)</p> <p>If however you need to have two instances of <code>Foo</code> that you construct when wiring up your application and then have the ability to say "This instance of Foo gets used when making a <code>Bar</code> or a <code>Baz</code>, whereas this other instance is used when making a <code>Bumble</code>", what you do is annotate the injection points and then when wiring up your app say something like:</p> <pre><code>Foo foo1 = new Foo("1"); Foo foo2 = new Foo("2"); bind(Foo.class).annotatedWith(Names.named("Bar")).toInstance(foo1); bind(Foo.class).annotatedWith(Names.named("Baz")).toInstance(foo1); bind(Foo.class).annotatedWith(Names.named("Bumble")).toInstance(foo2); </code></pre> <p>Where I assume that you've annotated the arguments to <code>Bar</code>'s constructor with something like:</p> <pre><code>public Bar(@Named("Bar") Foo foo) { ... </code></pre> <p>And similarly for <code>Baz</code> and <code>Bumble</code>. Of course, if you annotate the constructor of <code>Bar</code> and <code>Baz</code> with the same thing, you can skip one of the <code>bind</code> lines.</p> <p>I know there are annotation-processing frameworks for php based on reflection, or perhaps you can use a convention based on argument names.</p>

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