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🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 ✅ Streams : A sequence of elements supporting sequential and parallel aggregate operations ✨ stream() ✔️ Returns a sequential stream with this collection as its source import java.util.Arrays; import java.util.List; public class Main { public static void main(String[] args) { List people = Arrays.asLi..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 people 리스트 출력하기 for loop for-in loop for-each loop ✨ External Iterator · for & for-in loop import java.util.Arrays; import java.util.List; public class Main { public static void main(String[] args) { List people = Arrays.asList( new Person("Charles", "Dickens", 60), new Person("Lewis", "Carroll", 42),..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 ✨ No input arg. & Calling a method without any args ☑️ () → method() · Examples public class Main { public static void main(String[] args) { // no input argument & calling a method without any arguments // Thread t = new Thread(() -> printMessage()); -> method execution Thread t = new Thread(Main::pri..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 ✨ 'This' reference in Lambda · the instance of a lambda that does not touch 'this' reference → unmodified · no overriding ✨ Lambda vs. Anonymous Inner Class · Interface interface Process { void process(int i); } · Lambda : it still refers to the instance that it points to outside of the lambda public ..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 ✔️ Closure : 내부에서 외부 함수의 지역 변수 호출하기 · Code public class Main { public static void main(String[] args) { int a = 10; int b = 20; doProcess(a, i -> System.out.println(i + b)); } private static void doProcess(int i, Process p) { p.process(i); } } interface Process { void process(int i); } ➡️ main 함수에서 do..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 💡 someNumbers 배열 원소들을 key 값으로 나눈 나머지 출력하기 💡 · key 값이 2일 때 출력 (정상) · key 값이 0일 때 출력 (예외 상황) · Code import java.util.function.BiConsumer; public class Main { public static void main(String[] args) { int[] someNumbers = {1,2,3,4}; int key = 2; process(someNumbers, key, wrapperLambda((v, k) -> System.out...

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 🐣 Missions 🐣 ☝️ Sort list by last name ✌️ Create a method that prints all elements in the list 👌 Create a method that prints all people that have last name beginning with C 🐤 Solution 🐤 · Interface public class Person { private String firstName; private String lastName; private int age; public Person(..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 ✨ Lambda vs. Interface Implementations · Interface public interface Greeting { public void perform(); } · Interface Implementation public class GreetingImpl implements Greeting{ @Override public void perform() { System.out.println("Hello Java8"); } } · Main public class Main { public static void main(..

🤹‍♂️Java Brains 강의🤹‍♂️ https://www.youtube.com/playlist?list=PLqq-6Pq4lTTa9YGfyhyW2CqdtW9RtY-I3 ✨ Code in OOP ☑️ Object Oriented Programming (OOP) 에 문제가 있어서 Java8 Lambda 가 나온 것 (진짜?) · Everything is an object · All code blocks are 'associated' with classes and objects ✨ Why Lambdas? · Enables functional programming · Readable and concise code · Easier to use APIs and libraries · Enable support f..

🐣생활코딩 강의🐣 JAVA 제어문 https://www.youtube.com/playlist?list=PLuHgQVnccGMCoEXnWV8-UF1mBxK5ftmxH Looping Statement 🥚 반복문 기본 구조 · while · for public class Main { public static void main(String[] args) { System.out.println(1); int i = 0; System.out.println("=== while ==="); while(i < 3) { System.out.println(2); System.out.println(3); i++; } System.out.println("=== for ==="); for(int j = 0; j < 3; j++) ..