--- id: java-characters title: "Java Characters" category: "Programming_Language" status: "draft" verification_status: "conceptual" canonical_id: "" aliases: ["char type", "ASCII values", "자바 문자 타입"] 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", "char", "string", "ascii"] raw_sources: ["https://www.w3schools.com/java/java_data_types_characters.asp"] applied_in: [] github_commit: "" --- # [[Java Characters]] ## 🎯 한 줄 통찰 (One-line insight) A `char` can be assigned either a single-quoted character literal OR its raw ASCII integer value — `char myVar1 = 65;` prints "A" just as reliably as `char myVar1 = 'A';`, since char IS a numeric type under the hood. [S1] ## 🧠 핵심 개념 (Core concepts) - **`char`** — stores a single character, in single quotes (`'A'`). [S1] - **ASCII assignment** — a char can also be assigned its numeric ASCII value directly (e.g. `65` displays as `A`). [S1] - **`String`** — a sequence of characters (text), double-quoted; technically a NON-primitive type, since it refers to an object with methods. [S1] ## 🧩 추출된 패턴 (Extracted patterns) - **char is secretly numeric** — being able to assign `char myVar1 = 65;` and have it print `A` reveals that `char` is really a 16-bit numeric type interpreted as a character, not a distinct "letter" type. [S1] ## 📖 세부 내용 (Details) - Basic char: `char myGrade = 'B';`. [S1] - ASCII-based assignment: `char myVar1 = 65, myVar2 = 66, myVar3 = 67;` prints A, B, C. [S1] - String (non-primitive): `String greeting = "Hello World";`. [S1] ## ⚖️ 모순 및 업데이트 (Contradictions & updates) - **String은 원시 타입이 아님**: 소스에서 String을 "특별한 아홉 번째 타입"이라 부르면서도, 실제로는 객체를 참조하는 비원시 타입이라고 명시함 — 이는 8개 원시 타입 목록과 별개로 이해해야 한다. [S1] ## 🛠️ 적용 사례 (Applied in summary) 현재 발견된 실제 적용 사례가 없습니다 — String의 "객체"라는 개념은 이후 OOP/Classes 챕터에서 본격적으로 다뤄진다. [S1] ## 💻 코드 패턴 (Code patterns) char via ASCII value (Java): ```java char myVar1 = 65, myVar2 = 66, myVar3 = 67; System.out.println(myVar1); // A System.out.println(myVar2); // B System.out.println(myVar3); // C ``` ## ✅ 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 Data Types]], [[Java Strings]], [[Java Classes]] - **참조 맥락:** char가 숫자 타입의 일종이라는 점, String이 비원시(객체) 타입이라는 점의 첫 소개. ## 📚 출처 (Sources) - [S1] W3Schools — Java Characters — https://www.w3schools.com/java/java_data_types_characters.asp ## 📝 변경 이력 (Change history) - 2026-07-04: Initial draft synthesized from the W3Schools "Java Characters" page (Astra wiki-curation, P-Reinforce v3.1 format).