섹션 2. Object 클래스

[java.lang 패키지 소개](https://al1kite.notion.site/java-lang-1b19e42a8161800ea53aca9bbadf9f31)

[Object 클래스](https://al1kite.notion.site/Object-1b19e42a816180679807c1cdd60a7de0)

[Object 다형성](https://al1kite.notion.site/Object-1b19e42a816180fd9c63c26d717ad0a6)

[Object 배열](https://al1kite.notion.site/Object-1b19e42a816180dbad4ee93a82d8347b)

[toString()](https://al1kite.notion.site/toString-1b19e42a81618003881ef4cffc0e90a3)

[Object와 OCP](https://al1kite.notion.site/Object-OCP-1b19e42a8161809e9f39fac460b09d6a)

[equals() - 1. 동일성과 동등성](https://al1kite.notion.site/equals-1-1b19e42a816180188eedeacc88095e6a)

[equals() - 2. 구현](https://al1kite.notion.site/equals-2-1b19e42a816180b481c9d8915295f0e6)

[문제와 풀이](https://al1kite.notion.site/1b19e42a816180168c87c3a871b7502a)

[정리](https://al1kite.notion.site/1b19e42a816180de903df9e11cdc4946)

섹션 3. 불변 객체

[기본형과 참조형의 공유](https://al1kite.notion.site/1b19e42a8161802c933ce10e0248fa63)

[공유 참조와 사이드 이펙트](https://al1kite.notion.site/1b19e42a8161803ea08bd5b7f2f17f3b)

[불변 객체 - 도입](https://al1kite.notion.site/1b19e42a8161807abb88c63ce8a04c3b)

[불변 객체 - 예제](https://al1kite.notion.site/1b19e42a8161803bbdbdf6e55cf0e6e3)

[불변 객체 - 값 변경](https://al1kite.notion.site/1b19e42a816180ba92d6f6b95fee551e)

[문제와 풀이](https://al1kite.notion.site/1b19e42a816180239f7bc9d2332c71cd)

[정리](https://al1kite.notion.site/1b19e42a8161807a927dc5cd603b5caa)