Each object encapsulates its own attributes and methods so that other objects can access or change the attribute values only through the object's methods. For example, a Lady object would have age and salary attributes that can only be retrieved or set through get_age and set_salary methods. This hiding of attributes is a key aspect of encapsulation that distinguishes object-oriented applications from procedural ones, where data is stored independently of any object.

1. Material 11

2. Objects
Age: 35
methods (methods)
Attributes (values)
Set_salary (20)
Object: woman
method:
Set_salary
employer
Get_age
friend
Salary: 10

3. Encapsulation
• Each objects methods manage it’s own attributes.
• This is also known as hiding.
• An object A can learn about the values of
attributes of another object B, only by invoking
the corresponding method (message) associated to
the object B.
• Example:
– Class: Lady
– Attributes: Age, salary
– Methods: get_age, set_salary

4. Procedural vs. Object-Oriented
Procedural application OO-application
DATA
Line of code
Line of code
Line of code
Data is stored
independent
of application
Each object is independent of
the others