Java Basic - Files and I/O 10 minutes readThe java.io package contains nearly every class you might ever need to perform input and output (I/O) in Java.
Java Inheritance 4 minutes readInheritance allows code reuse in Object oriented programming language.
Java Encapsulation less than 1 minute readEncapsulation is one of four fundamental OOP concepts. The other three are inheritance, polymorphism, and abstraction.