The Observable design pattern is used in many important Java APIs. One well-known example is a JButton that uses the ActionListener API to execute an action. In this example, we have an ActionListener ...

Java NIO — the New Input/Output API package– was introduced with J2SE 1.4 in 2002. Java NIO’s purpose was to improve the programming of I/O-intensive chores on the Java platform. A decade later, many ...