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copied!<p>Nothing gets typecasted to <code>Class</code>. Every <code>Object</code> in Java belongs to a certain <code>class</code>. That's why the <code>Object</code> class, which is inherited by all other classes, defines the <code>getClass()</code> method.</p> <p><code>getClass()</code>, or the class-literal - <code>Foo.class</code> return a <code>Class</code> object, which contains some metadata about the class:</p> <ul> <li>name</li> <li>package</li> <li>methods</li> <li>fields</li> <li>constructors</li> <li>annotations</li> </ul> <p>and some useful methods like casting and various checks (<code>isAbstract()</code>, <code>isPrimitive()</code>, etc). <a href="http://download.oracle.com/javase/6/docs/api/java/lang/Class.html" rel="noreferrer">the javadoc</a> shows exactly what information you can obtain about a class.</p> <p>So, for example, if a method of yours is given an object, and you want to process it in case it is annotated with the <code>@Processable</code> annotation, then:</p> <pre><code>public void process(Object obj) { if (obj.getClass().isAnnotationPresent(Processable.class)) { // process somehow; } } </code></pre> <p>In this example, you obtain the metadata about the class of the given object (whatever it is), and check if it has a given annotation. Many of the methods on a <code>Class</code> instance are called "reflective operations", or simply "reflection. <a href="http://download.oracle.com/javase/tutorial/reflect/index.html" rel="noreferrer">Read here</a> about reflection, why and when it is used.</p> <p>Note also that enums and interfaces also represent a <code>Class</code> object, and have the respective metadata.</p> <p>To summarize - each object in java has (belongs to) a class, and has a respective <code>Class</code> object, which contains metadata about it, that is accessible at runtime.</p>

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