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. Abstract classes ...

Library authors would prefer to use interfaces to expose opaque abstractions; abstract classes were meant to be an implementation aid, not a modeling tool. (See Effective Java, "Prefer interfaces ...

simple Java class that can identify a person's location, find a center-point when multiple locations are provided, or even find clusters within a data set. One common aspect across all these methods ...