Can you explain the basic principles of encapsulation in object-oriented programming?

Encapsulation is one of the fundamental principles of object-oriented programming, which involves hiding the internal implementation of an object and providing access to data only through specific methods.

Key points:

• Data hiding: internal fields of an object are made private to prevent direct access from outside.
• Controlled access: providing public methods (getters and setters) for reading and modifying the state.
• Data integrity protection: methods can validate input data before changing the state.

Example in Python:

class Person:
    def __init__(self, name):
        self.__name = name  # private field

    def get_name(self):
        return self.__name

    def set_name(self, name):
        if isinstance(name, str) and name:
            self.__name = name
        else:
            raise ValueError("Name must be a non-empty string")

p = Person("Ivan")
print(p.get_name())  # Ivan
p.set_name("Peter")
print(p.get_name())  # Peter

Thus, encapsulation helps protect the object from incorrect usage and simplifies code maintenance.