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    <p>What you can do in such a case is having a proxy handler that will redirect calls to existing methods of your abstract class.</p> <p>You of course will have to code it, however it's quite simple. For creating your Proxy, you'll have to give him an <code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/reflect/InvocationHandler.html" rel="nofollow noreferrer">InvocationHandler</a></code>. You'll then only have to check the method type in the <code><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/reflect/InvocationHandler.html#invoke(java.lang.Object,%20java.lang.reflect.Method,%20java.lang.Object[])" rel="nofollow noreferrer">invoke(..)</a></code> method of your invocation handler. But beware : you'll have to check the method type against the underlying object associated to your handler, and not against the declared type of your abstract class.</p> <p>If I take as an example your dog class, your invocation handler's invoke method <strong>may</strong> look like this (with an existing associated dog subclass called .. well ... <code>dog</code>)</p> <pre><code>public void invoke(Object proxy, Method method, Object[] args) { if(!Modifier.isAbstract(method.getModifiers())) { method.invoke(dog, args); // with the correct exception handling } else { // what can we do with abstract methods ? } } </code></pre> <p>However, there is something that keep me wondering : I've talked about a <code>dog</code> object. But, as the Dog class is abstract, you can't create instances, so you have existing subclasses. Furthermore, as a rigorous inspection of Proxy source code reveals, you may discover (at Proxy.java:362) that it is not possible to create a Proxy for a Class object that does not represents an interface).</p> <p>So, apart from the <strong>reality</strong>, what you want to do is perfectly possible.</p>
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    1. POAlternatives to java.lang.reflect.Proxy for creating proxies of abstract classes (rather than interfaces)
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    1. USchatellier
    1. USRiduidel
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    1. COPlease bear with me while I try to understand your answer... In my particular case, I want the *proxy class* (generated at runtime) to be the subclass of `Dog` (for example, I'm not explicitly writing a `Poodle` class that implements `fetch()`). Therefore, there is no `dog` variable to invoke the methods upon... Sorry if I'm confusing, I will have to think this over a bit more.
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      1. USAdam Paynter
    2. CO@Adam - you can't dynamically create subclasses at runtime without some bytecode manipulation (CGLib I think does something like this). The short answer is that dynamic proxies support interfaces, but not abstract classes, because the two are very very different concepts. It's almost impossible to think of a way to dynamically proxy abstract classes in a sane way.
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      1. USAndrzej Doyle
    3. CO@Andrzej: I understand that what I'm asking for requires bytecode manipulation (in fact, I have already written a solution to my problem using ASM). I also understand that Java's dynamic proxies only support interfaces. Perhaps my question wasn't entirely clear - I am asking if there is *any other* class (that is, something other than `java.lang.reflect.Proxy`) available that does what I need.
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      1. USAdam Paynter
 

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