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    <p>You could use a bit more reflection to get it:</p> <pre><code>Method[] methods = stuffClass.getMethods(); for(Method m: methods) { if(m.getName().equals("doNiceStuff")) { Class&lt;?&gt; paramTypes = m.getParameterTypes(); //condition on the desired parameter types comes here if(paramTypes.length==1 &amp;&amp; A.class.isAssignableFrom(paramTypes[0]) { //we found it! } } } </code></pre> <p><strong>Why is isSuperClass() not good in this case?</strong></p> <p>Suppose we'd do it like this:</p> <pre><code>if (paramTypes.length == 1 &amp;&amp; paramTypes[0].getSuperclass().equals(A.class)) { ... </code></pre> <p>This solution would be good for the class <code>B</code>, but what if we have a class <code>C</code>?</p> <pre><code>public class C extends B { public void doNiceStuff(C arg0) { //do nice stuff here } } </code></pre> <p>This condition</p> <pre><code>paramTypes[0].getSuperclass().equals(A.class) </code></pre> <p>would be false! paramTypes[0].getSuperClass() is <code>B.class</code>, and is not equal to <code>A.class</code>...</p> <p><strong>Class.getMethods()</strong></p> <blockquote> <p>Returns an array containing Method objects reflecting all the public member methods of the class or interface represented by this Class object, including those declared by the class or interface and those inherited from superclasses and superinterfaces.</p> </blockquote> <p><strong>Class.isAssignableFrom()</strong></p> <blockquote> <p>Determines if the class or interface represented by this Class object is either the same as, or is a superclass or superinterface of, the class or interface represented by the specified Class parameter. It returns true if so; otherwise it returns false. If this Class object represents a primitive type, this method returns true if the specified Class parameter is exactly this Class object; otherwise it returns false. Specifically, this method tests whether the type represented by the specified Class parameter can be converted to the type represented by this Class object via an identity conversion or via a widening reference conversion. See The Java Language Specification, sections 5.1.1 and 5.1.4 , for details.</p> </blockquote> <p>Recommended reading:</p> <ul> <li><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Class.html" rel="nofollow">Class</a></li> <li><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/reflect/Method.html" rel="nofollow">Method</a></li> <li><a href="http://docs.oracle.com/javase/7/docs/api/java/lang/Class.html#isAssignableFrom%28java.lang.Class%29" rel="nofollow">isAssignableFrom</a></li> </ul>
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    1. COThanks for the information ppeterka. Although this solution fits the problem, I'm wondering why it couldn't be done with something like Class<? extends A>. How come that java isn't capable of figuring out the hierarcy?
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    2. COLook up type [java type erasure](http://docs.oracle.com/javase/tutorial/java/generics/genTypes.html). To be backwards compatible with Java <1.5, generics is more of a syntactic sugar. Very-very-very simplified: In runtime Class<X extends whatever> will just be used as Class...
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    3. COI've looked at isAssignableFrom() and if I understand it correctly it is just the opposite of what I'm trying to achieve. I have the superclass and I want to know if there is a method in dostuff which parameterlist expects a subclass of A (it expects B). the assignableFrom should no about the subclass and expect the superclass as parameter
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