Class in core Java

Everything in Java is associated with classes and objects, along with its attributes and methods . For example: in real life, a car is an object. The car has attributes, such as weight and color, and methods, such as drive and brake. A Class is like an object constructor, or a “blueprint” for creating objects.

The List interface provides four methods for positional (indexed) access to list elements . Lists (like Java arrays) are zero based. Note that these operations may execute in time proportional to the index value for some implementations (the LinkedList class, for example).

Java 8 includes four types of method references: A method reference to a static method . A method reference to an instance method of an arbitrary type . A method reference to an instance method of an existing object .