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copied!<p>To test whether <code>clazz</code> is a (sub) type of <code>MyClass</code> do</p> <pre><code>MyClass.class.isAssignableFrom(clazz) </code></pre> <p>From the javadoc for <a href="http://download.oracle.com/javase/6/docs/api/java/lang/Class.html#isAssignableFrom%28java.lang.Class%29" rel="nofollow"><code>Class.isAssignableFrom</code></a></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.</p> <p>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>So</p> <pre><code>Object.class.isAssignableFrom(String.class) </code></pre> <p>is true because each <code>String</code> is also an <code>Object</code> but</p> <pre><code>String.class.isAssignableFrom(Object.class) </code></pre> <p>is false because not all <code>Object</code>s are <code>String</code>s.</p> <hr> <p>The name "<code>isAssignableFrom</code>" comes from the fact that,</p> <pre><code>Class1 x = (Class2) null; </code></pre> <p>is only legal when</p> <pre><code>Class1.class.isAssignableFrom(Class2.class) </code></pre> <p>I.e., we can <strong>assign</strong> a field or variable with static type <code>Class1</code> a value that comes <strong>from</strong> an expression whose static type is <code>Class2</code>.</p>

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