> For the complete documentation index, see [llms.txt](https://incheol-jung.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6.md).

# 메서드

- [아이템49 매개변수가 유효한지 검사하라](https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6/49.md): Effective Java 3e 아이템 49를 요약한 내용 입니다.
- [아이템50 적시에 방어적 본사본을 만들라](https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6/50.md): Effective Java 3e 아이템 50를 요약한 내용 입니다.
- [아이템53 가변인수는 신중히 사용하라](https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6/53.md): Effective Java 3e 아이템 53를 요약한 내용 입니다.
- [아이템 54 null이 아닌, 빈 컬렉션이나 배열을 반환하라](https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6/54-null.md): Effective Java 3e 아이템 54를 요약한 내용 입니다.
- [아이템56 공개된 API 요소에는 항상 문서화 주석을 작성하라](https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6/56-api.md): Effective Java 3e 아이템 56를 요약한 내용 입니다.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://incheol-jung.gitbook.io/docs/study/effective-java/undefined-6.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.
