PROPS img import reactImg from './assets/exam.png'; function App() { return ( {/* public 폴더에 sample.png 붙여넣기 할것*/} ); }; export default App; PROPS index.js 에서 막으면 결과가 출력 한번만 됨 import React from 'react'; import ReactDOM from 'react-dom/client'; import './index.css'; import App from './App.js'; import reportWebVitals from './reportWebVitals'; const root = ReactDOM.createRoot(document.getElementByI..

collection_list @SpringBootApplication /// 서브패키지에 있는 @JavaConfig 자동생성함 public class Sample01BeanApplication { public static void main(String[] args) { ApplicationContext ctx=SpringApplication.run(Sample01BeanApplication.class, args); DBService service= ctx.getBean("myService", DBService.class); List list= service.list(); System.out.println(list.size()); for (String s : list) { //List data= dao.l..

함수 유틸리티 함수 var kkk = setInterval(function(){ console.log("setInterval") },3000) //3초에 한번씩 실행됨 setTimeout(function(){ alert("니코짱") clearInterval(kkk) } , 10000) //10초 뒤에 외부함수 var a = function(arg){ var b= function(n){ return n*100 } return b(arg) } var result = a(2) console.log(result) →200 function x(arg){ function y(n){ return n*10 } return y(arg) } var result = x(3) console.log(result) →300 cl..

3. Comparator -> ArrayList 정렬 System.out.println("======= itrator 이용 순회"); Iterator ite = list.iterator(); while(ite.hasNext()) { System.out.println(ite.next()); } System.out.println(list.size()); System.out.println(list); for (int i = 0; i < list.size(); i++) { Object o=list.get(i); String s = (String)o; System.out.println(s); } 3 [홍길동, 이순신, 홍길동] 홍길동 이순신 홍길동 System.out.println("길이(크기)"+list.siz..