java Android kotlin 특징 open class MultiProcess JavaVirtualMachine intentflag LinkedHashSet Kotilin Kotiln POJO Class AutoUnBoxing 4대 컴포넌트 immutable 미세먼지앱 Lottie autoboxing 임계 구역 공공데이터포털 memoryleak Wrapper class FIFO boilerplate treemap overhead oom Intent MVVM MultiThread Abstract Class Ranges 멀티프로세스 Critical Section lambda DataBinding TreeSet 데드락 HashSet BufferedWriter BufferedReader synchronized IOC LinkedList 기본 문법 Deadlock 세미콜론 Val StringBuffer var mutable 오버헤드 LIFO 메모리누수 boxing null POJO 멀티스레드 LinkedHashMap context unboxing HashMap Di Any JVM stack arrayList queue class Process Loop 자료구조 map Thread Let When