Creating classes: declarations, fields, and constructors

A class declaration lists, in order: modifiers such as public or private, the class name capitalized by convention, an optional superclass after extends (a class can only extend one parent), and implemented interfaces after implements (more than one allowed), before the brace-surrounded class body. The class body provides the life cycle of objects: constructors initialize new objects, field declarations provide state, and methods implement behavior. Declare fields with zero or more modifiers, a type, and a name; fields are member variables in a class, distinct from local variables in a method or block and parameters in method declarations. In the spirit of encapsulation, it is common to make fields private, exposing values indirectly through public methods. Scope: Java. Reviewed October 4, 2026.