The Principles of Encapsulation and Information Hiding
- Encapsulation is the practice of bundling (or encapsulating) data and methods that operate on that data within a single unit, typically a class.
- This ensures that the internal workings of the class are hidden from the outside world.
- Information Hiding is a related concept that focuses on restricting access to certain parts of an object's data or implementation details.
- This is achieved by using access modifiers to control which parts of a class are visible to other parts of the program.
- Encapsulation and information hiding are often used interchangeably, but they have distinct roles.
- Encapsulation is the broader concept of bundling data and methods, while information hiding specifically refers to restricting access to certain parts of a class.
Applying Access Modifiers: Private and Public
Access modifiers are keywords that define the visibility of class members (variables and methods).
The most common access modifiers are:
- Private:
- Members declared as private are accessible only within the class itself.
- This is the default access level for instance variables in encapsulated classes.
- Public:
- Members declared as public are accessible from any other class.
- This is typically used for methods that need to be called from outside the class.
- In Java, access modifiers are explicit (e.g.,private,public), while in Python, they are more convention-based.
- A single underscore (e.g.,_variable) indicates a protected member, while a double underscore (e.g.,__variable) indicates a private member.
Controlling Access to Class Members
Encapsulation is achieved by controlling access to class members through a combination of private variables and public methods.
