Added real world example for Composite.

README.md

@@ -143,6 +143,7 @@
 * you want clients to be able to ignore the difference between compositions of objects and individual objects. Clients will treat all objects in the composite structure uniformly
 
 **Real world examples:**
+* [java.awt.Container](http://docs.oracle.com/javase/6/docs/api/java/awt/Container.html) and [java.awt.Component](http://docs.oracle.com/javase/6/docs/api/java/awt/Component.html)
 * [Apache Wicket](https://github.com/apache/wicket) component tree, see [Component](https://github.com/apache/wicket/blob/91e154702ab1ff3481ef6cbb04c6044814b7e130/wicket-core/src/main/java/org/apache/wicket/Component.java) and [MarkupContainer](https://github.com/apache/wicket/blob/b60ec64d0b50a611a9549809c9ab216f0ffa3ae3/wicket-core/src/main/java/org/apache/wicket/MarkupContainer.java)
 
 ## <a name="decorator">Decorator</a> [&#8593;](#list-of-design-patterns)