What's the Difference Between Public, Private, and Protected Access Modifiers in OOP?

Access Control in OOP: Understanding the Differences Between Public, Private, and Protected

When defining classes in object-oriented programming, it's essential to understand the different access modifiers used to control the visibility of class members. Three primary modifiers are public, private, and protected, each serving a distinct purpose.

Public

Public members are accessible from anywhere within the scope of the class, including outside classes and objects. They can be accessed directly through the instance or using getters and setters. They're commonly used for properties and methods that need to be exposed to external entities.

Private

Private members are restricted to the internal scope of the class only. They can be accessed only within the methods of the same class. No outside class or object can directly access them. Private properties and methods enhance encapsulation and protect sensitive data.

Protected

Protected members fall between public and private. They are accessible from the class they're declared in, as well as from its derived or child classes. They provide access within the inheritance hierarchy without exposing methods or properties to external sources. Protected visibility is primarily used for properties and methods that should be inherited by child classes but should not be accessible outside the inheritance chain.

Choosing the Appropriate Modifier

The choice of access modifier depends on the intended use of the class member. As a general rule:

• Public: Use for properties or methods commonly used and accessible from external sources.
• Private: Use for sensitive data or methods that should be confined within the class.
• Protected: Use for properties or methods that should be accessible to derived classes but not external sources.

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