---
id: java-constants-final
title: "Java Constants Final"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["final keyword", "자바 상수"]
duplicate_of: ""
source_trust_level: "B"
confidence_score: 0.9
created_at: 2026-07-04
updated_at: 2026-07-04
review_reason: ""
merge_history: []
tags: ["java", "programming", "w3schools", "final", "constants"]
raw_sources: ["https://www.w3schools.com/java/java_variables_final.asp"]
applied_in: []
github_commit: ""
---

# [[Java Constants Final]]

## 🎯 한 줄 통찰 (One-line insight)
`final` variables are conventionally written in UPPER_CASE (e.g. `BIRTHYEAR`) — a style-only convention, not enforced by the compiler, but a strong readability signal that a value is a true constant. [S1]

## 🧠 핵심 개념 (Core concepts)
- **`final` keyword** — makes a variable a constant: unchangeable and read-only. [S1]
- **Reassignment error** — attempting to change a final variable raises a compile error. [S1]
- **When to use** — for values that should never change (minutes per hour, a birth year). [S1]
- **Naming convention** — final variables are usually written in UPPER_CASE (not enforced, just convention). [S1]

## 📖 세부 내용 (Details)
- Basic final: `final int myNum = 15; myNum = 20; // Error`. [S1]
- Named constants: `final int MINUTES_PER_HOUR = 60; final int BIRTHYEAR = 1980;`. [S1]

## ⚖️ 모순 및 업데이트 (Contradictions & updates)
소스에서 모순되는 정보는 발견되지 않음.

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 절대 변경되지 않아야 하는 값(설정값, 물리 상수 등)에 표준적으로 쓰인다. [S1]

## 💻 코드 패턴 (Code patterns)
Named constants with final (Java):
```java
final int MINUTES_PER_HOUR = 60;
final int BIRTHYEAR = 1980;
```

## ✅ 검증 상태 및 신뢰도
- **상태:** draft
- **검증 단계:** conceptual
- **출처 신뢰도:** B (W3Schools — widely used educational reference, not a primary standards body)
- **신뢰 점수:** 0.90
- **중복 검사 결과:** 신규 생성 (New discovery)

## 🔗 지식 그래프 (Knowledge Graph)
- **상위/루트:** [[Java Tutorial]]
- **관련 개념:** [[Java Variables]], [[Java Modifiers]]
- **참조 맥락:** 불변 값을 강제하는 표준 도구 — Modifiers 챕터에서 다른 접근 제어자와 함께 다뤄진다.

## 📚 출처 (Sources)
- [S1] W3Schools — Java Constants (final) — https://www.w3schools.com/java/java_variables_final.asp

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