MainWrapper
package ex02_List;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;
public class MainWrapper {
public static void ex01()
{
List<String>season;
season=new ArrayList<String>();
season.add("여름");
season.add("가을");
season.add("겨울");
season.add(0,"봄");//위치, 요소
for(int i=0,length=season.size();i<length;i++)
{
System.out.println(season.get(i));
}
}
public static void ex02() {
List<String> hobbies =new ArrayList<String>();
hobbies.add("여행");
hobbies.add("코딩");
hobbies.add("독서");
System.out.println(hobbies.size());
System.out.println("----");
System.out.println(hobbies.get(hobbies.size()-1));
System.out.println("----");
for(int i=0,length=hobbies.size();i<length;i++)
{
System.out.println(hobbies.get(i));
}
}
public static void ex03() {
List<String>flower=new ArrayList<String>();
Scanner scan=new Scanner(System.in);
for(int i=1;i<4;i++)
{
flower.add(scan.next());
}
System.out.println("↓");
flower.set(0, "다투라");
//조회
for(int i=0,length=flower.size();i<length;i++) {
System.out.println(flower.get(i));
}
flower.remove(1);
System.out.println("↓");
//조회
for(int i=0,length=flower.size();i<length;i++) {
System.out.println(flower.get(i));
}
}
public static void ex04() {
Integer[] a= {10,20,30,40,50};
//배열을 ArrayList로 바꿈
List<Integer>numbers=Arrays.asList(a);
//초기화된 ArrayList는 길이변경불가
for(int i=0,length=numbers.size();i<length;i++)
{
System.out.println(numbers.get(i));
}
}
public static void ex05() {
//ArrayList 초기화
List<Integer>numbers=Arrays.asList(10,20,30,40,50);
//for문
for(int i=0,length=numbers.size();i<length;i++)
{
System.out.println(numbers.get(i));
}
}
public static void main(String[] args) {
ex01();
System.out.println("----");
ex02();
System.out.println("----");
ex03();
System.out.println("----ex05결과와 비교하기");
ex04();
System.out.println("----");
ex05();
}
scanner 입력
장미
다투라
능소화
출력결과
벨로그주소:https://velog.io/@000000hj
깃허브 주소
https://github.com/000000hj/MyPractice/tree/main/11_CollectionFramework
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