Object Oriented Concepts

Objects are entities that contain data and behaviors.

Objects contain methods that operate on the data types or attributes (encapsulation).

Class - a template from which objects are made. It is a blueprint for an object.

Instantiated - when objects are created they are instantiated.

Class is the table definition with the rows in the table being the objects. A cookie cutter is the class - the cookies are the objects.

Public & private attributes & methods.

• Public - other objects can directly access the attribute or method
• Private - only that specific object can access it directly.
• Protected - only related objects can access it directly.

Encapsulation

• Interfaces - normally do not include attributes only methods (If a user needs access to an attribute, then a method is created to return the value of the attribute. In this way the attribute is encapsulated in the object.
• Implementations - The implementation can change without effecting the interface and therefore without effecting the user's code.