Abstract classes and interfaces in Java serve fundamentally different purposes. Learn the differences between these Java language elements and how to use them in your programs.

Most introductory Java texts take an implementation-centric stab at how to use interfaces and abstract classes. However, few provide a clear design distinction for choosing between these two ...

However, there are collection classes in Java that act like a Java array but resize themselves automatically. Any class that extends the List interface expands dynamically. Java arrays do not expand ...