---
id: java-intro
title: "Java Intro"
category: "Programming_Language"
status: "draft"
verification_status: "conceptual"
canonical_id: ""
aliases: ["Java Introduction", "자바 소개"]
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", "basics"]
raw_sources: ["https://www.w3schools.com/java/java_intro.asp"]
applied_in: []
github_commit: ""
---

# [[Java Intro]]

## 🎯 한 줄 통찰 (One-line insight)
Java (1995, owned by Oracle, running on 3+ billion devices) is a platform-independent, object-oriented language whose syntactic closeness to C++/C# makes cross-language switching relatively easy. [S1]

## 🧠 핵심 개념 (Core concepts)
- **Origin** — created in 1995, owned by Oracle. [S1]
- **Use cases** — mobile (especially Android), desktop, web applications, web/app servers, games, database connections. [S1]
- **Cross-platform** — runs on Windows, Mac, Linux, Raspberry Pi, etc. [S1]
- **Object-oriented** — gives programs clear structure and reusable code, lowering development cost. [S1]
- **Similarity to C++/C#** — makes switching between these languages easier. [S1]
- **Free and open-source**, with large community support. [S1]

## 📖 세부 내용 (Details)
- Hello World example: [S1]
```java
public class Main {
    public static void main(String[] args) {
        String name = "John";
        System.out.println("Hello " + name);
    }
}
```

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

## 🛠️ 적용 사례 (Applied in summary)
현재 발견된 실제 적용 사례가 없습니다 — 이후 Syntax 챕터에서 이 Hello World 예제의 각 구성요소가 상세히 설명된다. [S1]

## 💻 코드 패턴 (Code patterns)
Hello World (Java):
```java
public class Main {
    public static void main(String[] args) {
        System.out.println("Hello " + "John");
    }
}
```

## ✅ 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 Syntax]], [[Java OOP]]
- **참조 맥락:** Java 튜토리얼 전체의 진입점.

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

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