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Classes and Objects
Classes
Declaring Classes
Declaring Member Variables
Defining Methods
Providing Constructors for Your Classes
Passing Information to a Method or a Constructor
Objects
Creating Objects
Using Objects
More on Classes
Returning a Value from a Method
Using the this Keyword
Controlling Access to Members of a Class
Understanding Instance and Class Members
Initializing Fields
Summary of Creating and Using Classes and Objects
Questions and Exercises
Questions and Exercises
Nested Classes
Inner Class Example
Summary of Nested Classes
Questions and Exercises
Enum Types
Questions and Exercises
Annotations
Questions and Exercises
Trail: Learning the Java Language
Lesson: Classes and Objects

> With the knowledge you now have of the basics of the Java programming language, you can learn to write your own classes. In this lesson, you will find information about defining your own classes, including declaring member variables, methods, and constructors.

> You will learn to use your classes to create objects, and how to use the objects you create.

> This lesson also covers nesting classes within other classes, enumerations, and annotations.

> ### Classes

> > This section shows you the anatomy of a class, and how to declare fields, methods, and constructors.

> ### Objects

> > This section covers creating and using objects. You will learn how to instantiate an object, and, once instantiated, how to use the `dot` operator to access the object's instance variables and methods.

> ### More on Classes

> > This section covers more aspects of classes that depend on using object references and the `dot` operator that you learned about in the preceding section: returning values from methods, the `this` keyword, class vs. instance members, and access control.

> ### Nested Classes

> > Static nested classes, inner classes, anonymous inner classes, and local classes are covered.

> ### Enum Types

> > This section covers enumerations, specialized classes that allow you to define and use sets of constants.

> ### Annotations

> > Annotations allow you to add information to your program that is not actually part of the program. This section describes three built-in annotations that you should know about.

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