docs(10_Wiki): Dev 폴더 누락분 반영 — Topic_Programming으로 통합

이전 재구성 작업에서 Dev/ 폴더가 누락되었던 것을 반영.

- Dev/Topic_Programming(중첩 폴더, 78개)은 Dev 자체 최상위 폴더들
  (Architecture/Conventions/Engineering_Intelligence 등)과 완전 중복이라 제거.
- Dev 최상위 엔지니어링 지식 폴더(Architecture/Conventions/Engineering_Intelligence/
  Failure_Library/Generalized_Principles/Language/Pattern_Catalog/Platform_Guides/
  Subsystems, 77개)는 이미 Topic_Programming/Topic_Programming에 더 최신 버전이
  존재해 중복 제거(고유 콘텐츠 1개는 예외 처리하여 이동 보존).
- Dev의 W3Schools 언어 튜토리얼 폴더(Topic_C/CPP/CSS/CSharp/HOWTO/HTML/Java/
  JavaScript/PHP/Python/SQL/W3CSS, 1201개)는 전부 Topic_Programming 하위로 이동.
- 에이전트 운영 상태(.astra/docs)는 그대로 유지, 콘텐츠 폴더만 정리.
- Topic_Programming 최종 문서 수: 2784 → 3985.

10_Wiki/Topic_Programming/Topic_Java/Java_Strings.md

@@ -0,0 +1,78 @@
+---
+id: java-strings
+title: "Java Strings"
+category: "Programming_Language"
+status: "draft"
+verification_status: "conceptual"
+canonical_id: ""
+aliases: ["자바 문자열"]
+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", "strings"]
+raw_sources: ["https://www.w3schools.com/java/java_strings.asp"]
+applied_in: []
+github_commit: ""
+---
+
+# [[Java Strings]]
+
+## 🎯 한 줄 통찰 (One-line insight)
+A Java String is an object with methods, not a raw character array — `length()`, `indexOf()`, `charAt()`, `equals()`, and `trim()` are all method calls (`str.method()`), not built-in functions like Python's `len(str)`. [S1]
+
+## 🧠 핵심 개념 (Core concepts)
+- **String** — a double-quoted, object-based text container in Java (not a primitive). [S1]
+- **`length()`** — returns character count. [S1]
+- **`toUpperCase()` / `toLowerCase()`** — case conversion. [S1]
+- **`indexOf(text)`** — position of the first occurrence (0-indexed). [S1]
+- **`charAt(index)`** — the character at a specific position. [S1]
+- **`equals(other)`** — compares string CONTENT, unlike `==` which compares references. [S1]
+- **`trim()`** — removes leading/trailing whitespace. [S1]
+
+## 🧩 추출된 패턴 (Extracted patterns)
+- **Method-call syntax throughout** — every string operation is `str.method()`, contrasting with Python's mix of methods (`str.upper()`) and built-in functions (`len(str)`). [S1]
+- **`equals()` not `==`** — the tutorial specifically teaches `equals()` for string comparison, implying `==` would compare object references rather than content (a classic Java gotcha, though not elaborated here). [S1]
+
+## 📖 세부 내용 (Details)
+- Length: `String txt = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"; txt.length()`. [S1]
+- Case conversion: `txt.toUpperCase(); txt.toLowerCase();`. [S1]
+- Find position: `String txt = "Please locate where 'locate' occurs!"; txt.indexOf("locate"); // 7`. [S1]
+- Character access: `String txt = "Hello"; txt.charAt(0); // H`. [S1]
+- Content comparison: `txt1.equals(txt2)`. [S1]
+- Trim whitespace: `String txt = " Hello World "; txt.trim(); // "Hello World"`. [S1]
+
+## ⚖️ 모순 및 업데이트 (Contradictions & updates)
+소스에서 모순되는 정보는 발견되지 않음.
+
+## 🛠️ 적용 사례 (Applied in summary)
+현재 발견된 실제 적용 사례가 없습니다 — 이후 Concatenation/Numbers and Strings/Special Characters 챕터에서 문자열 조작이 심화된다. [S1]
+
+## 💻 코드 패턴 (Code patterns)
+Content comparison with equals() (Java):
+```java
+String txt1 = "Hello";
+String txt2 = "Hello";
+System.out.println(txt1.equals(txt2));  // true
+```
+
+## ✅ 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 Strings Concat]], [[Java Strings Numbers]], [[Java Characters]]
+- **참조 맥락:** 문자열 메서드의 기초 — equals()로 내용 비교(==와 구분)해야 함이 핵심.
+
+## 📚 출처 (Sources)
+- [S1] W3Schools — Java Strings — https://www.w3schools.com/java/java_strings.asp
+
+## 📝 변경 이력 (Change history)
+- 2026-07-04: Initial draft synthesized from the W3Schools "Java Strings" page (Astra wiki-curation, P-Reinforce v3.1 format).