✅ Explain the structure of the JVM JVM: runtime engine that enables Java bytecode to be executed on any platform ClassLoader: load .class file into JVM Runtime data Area: memory Execution...

✅ Docker file docker file: file to create docker image docker image is created using docker file 이미 만들어진 image가 아니라, 내가 원하는 이미지를 만들고 싶을 수 있음 이때 사용하는 것이 docker file ☑️ FROM create ba...

✅ Docker volume command: -v volume: to save data on host memory can keep data regardless of container instead of container, save data on host memory ⚠️ if not use volume, when c...

✅ concurrency과 parralelism의 차이 concurrency: single core, multi thread, process takes turn looks like several jobs are done at the same time, but actually one job is done at once ...

✅ create image, container and run container -- create image, container and run container docker run nginx docker run mysql -- run docker in background run nginx -d nginx -- name container docker...

✅ JCF란 무엇인가요? Java collection framework handle data efficiently ✅ JCF의 계층 구조를 설명해주세요 Collection interface: List, Queue, Set Map: Map ✅ Map 인터페이스는 왜 Collection 인터페이스에 상속을 받지 않았나요...

✅ String literal과 new String(““)의 차이 String literal: saved in constant pool new String(""): saved in memory heap constant pool에 저장되면 동일한 문자열에 대해서는 하나의 참조를 재사용 constant pool에서는 같은 ...

✅ Charecteristics of Java OOP Polymorphism: single function can behave differently depending on the context, overriding(dynamic, runtime) and overloading(static, compile time) ...

✅ Why use docker? 각 프로그램을 독립적인 컨테이너 환경에 이미지로 패키징하여 실행 Portability: can install program regardless of environment no collision among other programs solves “it works on my machine” probl...

✅ Scope how many instances of a bean Spring should create and how long they should live 빈이 존재부터 언제까지 존재하는지 존재할 수 있는 범위 ✔️ singleton: default. One instance per Spring container. ✔️ pro...