See the Java 101 Java interfaces tutorial for a more in-depth introduction to using interfaces in your Java programs, including where and where not to use default, static, and private methods.

Abstract classes can contain abstract methods, which are methods that are declared but do not have a body. An abstract class is used as a base class to provide a common interface and implementation to ...

What is an Abstract Class? An abstract class is a class that is declared abstract —it may or may not include abstract methods. Abstract classes cannot be instantiated, but they can be subclassed. An ...

The Positional Shape Hierarchy: Let's now deal with a more complicated example of a positional shape inheritance hierarchy. It is illustrated below graphically; the superscript A is used to denote ...

Interface with default methods in java 8in later version of java interfaces always contained only method declaration. we are not giving method definition in the interfaces because java did not allow ...