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Computer Science a method in a class, it is like a method have access to or can modify
in an OOP where objects use methods to
sensitive data. In our example of the
pet dog house, protection prevents
access and modify data. In this example,
someone from directly accessing the
to protect a dog is like to protect data. I
dog’s bedroom (data) from outside
hope you will not like people to reach
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your dog easily in this house and take or
kill it. The idea of encapsulation achieves the house (class). A house as an
object is also an instance of a class.
this by making one attribute, like a dog’s (ii) Controlled modifications: The dog’s
bedroom, private. The other method in door (methods) regulates how the
this class is a feeding plan method. This dog interacts with the surrounding
is the authorised method that can interact environment. Similarly, methods
with the dog through other method (dog’s can enforce rules regarding data
door). In this example, a dog is like data. modifications. For example, a
method for supplying food may only
allow for a measured quantity to be
given to the dog.
(iii) Information hiding: You do not
need to be aware of the inner
workings of the dog door mechanism
(internal details) in order to use it.
Encapsulation hides the internal
implementation details of a class.
Instead, you interact with the
Figure 4.2: Encapsulation methods (dog’s door) to achieve
what you intended (feeding the dog).
In this case, encapsulation in OOP refers (iv) Flexibility: Assume you wish to add
to the practice of bundling data and an area for scratching to the playroom
the methods that operate on that data (an internal change). Encapsulation
within a single unit, typically a class. It allows you to change the house’s
involves hiding the internal details of an interior (class structure) without
object and providing a public interface impacting how people interact with
to interact with it. Encapsulating data the dog house (object). They still
and methods together ensures that the utilize the dog door (methods).
object’s state is accessed and modified
only through defined methods, known as Exercise 4.2
getters and setters.
1. How does the concept of
Importance of encapsulation in OOP encapsulation help in maintaining
(i) Data protection: Encapsulation data integrity and promoting
ensures that only authorised methods information hiding?
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for Advanced Secondary Schools
Computer Science Form 5.indd 214 23/07/2024 12:33
