How to Implement a Class on the AP CSA Exam

Class

Class

A blueprint for creating objects in Java, containing fields (attributes) and methods (behaviors).

Object

An instance of a class, representing a specific entity with state and behavior.

Field (Instance Variable)

A variable defined in a class to store data for each object. Typically private for encapsulation.

Constructor

A special method used to initialize objects, having the same name as the class and no return type.

Accessor Method (Getter)

A method that retrieves the value of a private field.

Mutator Method (Setter)

A method that modifies the value of a private field, often with input validation.

Encapsulation

The principle of restricting access to a class's fields by using private fields and public methods.

Method

A block of code within a class that performs a specific task when called.

this Keyword

A reference to the current object, often used to distinguish between fields and parameters with the same name.

Overloading

Defining multiple methods with the same name but different parameter lists within the same class.

toString Method

A method that returns a string representation of an object, often used for debugging or output.

Edge Case

An unusual or extreme input that tests the robustness of a program, such as negative numbers or null values.

Private Access Modifier

A keyword that restricts access to a field or method to within the class where it is declared.

Public Access Modifier

A keyword that allows access to a field or method from anywhere in the program.

Return Type

Specifies the data type of the value a method will return, or void if no value is returned.

Parameter

A variable in a method or constructor declaration used to pass values into the method or constructor.

Default Constructor

A no-argument constructor provided by Java if no other constructors are defined in the class.

Null

A special value representing an object reference that does not point to any object.

Static Method

A method associated with the class rather than any instance, called using the class name.

Instance Method

A method that operates on an instance of a class, requiring an object to be called.