---
id: cpp-inheritance-access
title: "C++ Inheritance Access"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["protected access specifier", "C++ 상속과 protected"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.86
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["cpp", "programming-language", "w3schools", "oop", "inheritance", "protected"]
raw_sources: ["https://www.w3schools.com/cpp/cpp_inheritance_access.asp"]
applied_in: []
github_commit: ""
---

# [[CPP Inheritance Access]]

## 🎯 한 줄 통찰 (One-line insight)
This chapter reveals WHY `protected` exists as a third option distinct from `private`: a `private` attribute in the base class would be completely UNREACHABLE by the derived class's own methods, forcing awkward workarounds, while `protected` lets `Programmer`'s `setSalary()`/`getSalary()` methods directly manipulate `Employee`'s `salary` field as if it were their own — meaning `protected` specifically solves the "I need child classes to touch this, but nobody else" access pattern that neither `public` nor `private` alone can express. [S1]

## 🧠 핵심 개념 (Core concepts)
- **`protected`** — similar to `private` (inaccessible from OUTSIDE the class), but UNLIKE `private`, accessible from DERIVED (child) classes. [S1]
- **Derived-class methods manipulating a protected base attribute** — `Programmer`'s `setSalary()`/`getSalary()` methods read/write `Employee`'s `protected int salary;` directly, as if it belonged to `Programmer`. [S1]

## 📖 세부 내용 (Details)
- A protected base attribute manipulated by a derived class's own methods: `class Employee { protected: int salary; }; class Programmer: public Employee { public: int bonus; void setSalary(int s) { salary = s; } int getSalary() { return salary; } }; Programmer myObj; myObj.setSalary(50000); myObj.bonus = 15000;`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
- **protected는 private과 public 사이의 중간 지점**: 클래스 외부에서는 접근 불가하다는 점에서 private과 같지만, 파생 클래스에서는 접근 가능하다는 점에서 다르다는 것이 확인됨 — 이는 private만으로는 해결 못 하는 "자식 클래스만 접근 허용" 요구를 해결. [S1]

## 🛠️ 적용 사례 (Applied in summary)
Employee의 protected 급여(salary)를 Programmer 파생 클래스가 자체 getter/setter로 직접 다루는 예제가 protected의 대표 실전 활용 사례로 원문에 직접 제시됨. [S1]

## 💻 코드 패턴 (Code patterns)
A protected base attribute directly manipulated by a derived class's own methods (C++):
```cpp
class Employee {
protected: // accessible in derived classes, not outside
  int salary;
};
class Programmer: public Employee {
public:
  int bonus;
  void setSalary(int s) { salary = s; }
  int getSalary() { return salary; }
};
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.86
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[C++ Tutorial]]
- **관련 개념:** [[CPP Inheritance]], [[CPP Access Specifiers]], [[CPP Inheritance Multilevel]]
- **참조 맥락:** 상속과 protected — 다단계 상속(Inheritance Multilevel) 챕터로 이어짐.

## 📚 출처 (Sources)
- [S1] W3Schools — C++ Inheritance Access — https://www.w3schools.com/cpp/cpp_inheritance_access.asp

## 📝 변경 이력 (Change history)
- 2026-07-04: Initial draft synthesized from the W3Schools "C++ Inheritance Access" page (Astra wiki-curation, P-Reinforce v3.1 format).