Encapsulation and Object-Level Access in OOP

Object-oriented programming (OOP) is designed around the concept of encapsulation, which restricts access to an object's private fields to the class that defines them. 그러나 주어진 코드 스 니펫에서는 다른 사람 객체의 계정 개인 필드에 액세스 할 수 있습니다. This behavior raises the question:

Why does OOP allow class-level access to private fields rather than object-level access?

The answer lies in the design principles of OOP and the advantages of limiting access to specific objects.

According to Artemix, who provided an insightful response on another forum, the private modifier 캡슐화 원리를 시행합니다. 내부 프로세스가 시간이 지남에 따라 변경 될 수 있으므로 외부 엔티티가 객체의 내부 상태를 수정할 수 없도록합니다. If external code could access private fields, any changes to those processes would require modifying all external code, making maintenance and evolution difficult.

By restricting access to class-level, instances of the same class are always aware of the implementation details of their private methods and fields. This simplifies code maintenance and ensures consistency across all instances.

In other words, object-level access would allow external code to manipulate an object's state in unexpected ways, potentially leading to inconsistencies and bugs. Class-level access, on the other hand, allows the object itself to control access to its private fields, ensuring that only authorized methods can modify its internal state.