Using an anonymous class to pass functionality as a method argument (Comparer.java) public abstract class Comparer { public abstract int compare(int x, int y); } ...

Readers have returned quite a bit of feedback concerning, “Abstract Classes Vs. Interfaces” from April 2001. A recurring request asks to see a complete example of using interfaces and abstract ...

Sealed classes make Java an even more powerful and expressive language and set the stage for even more sophisticated techniques such as pattern matching, which we'll explore in a subsequent article. A ...