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Java??????List???Collection??????List???????Collection???????????????????????????????????????List???????????????ArrayList?LinkedList?

List???????

List???????Collection???????????????????????????????????????????????????????????????

List???????

List??????????????????

List????

???????List?????ArrayList?LinkedList???ArrayList????????????????????????????????????LinkedList?????????????????????????????

List?????

• ArrayList???????????????????????????????????
• LinkedList?????????????????????????????????

List?????

List??????????????

Iterator

2. ??for???

for (Object o : list) {
    System.out.println(o);
}

3. ??for?????????

for (int i = 0; i < list.size(); i++) {
    System.out.println(list.get(i));
}

????

???????ArrayList??????

import org.junit.Test;
import java.util.ArrayList;
import java.util.Date;
public class ListTest {
    @Test
    public void listTest() {
        ArrayList
     
       list = new ArrayList<>();
        list.add(1);
        list.add(2);
        list.add(3);
        System.out.println("?????" + list);
        // ??add(int index, Object ele)????
        list.add(1, 4);
        System.out.println("???1??????" + list);
        // ??addAll(int index, Collection eles)??????
        ArrayList
      
        list2 = new ArrayList<>();
        list2.add(5);
        list2.add(6);
        list.addAll(3, list2);
        System.out.println("???3????2?????" + list);
        // ?????????
        System.out.println("??2????" + list.get(2));
        // ???????
        System.out.println("??5????" + list.indexOf(5));
        System.out.println("??7????" + list.indexOf(7)); // -1?????
        // ?????????
        System.out.println("????2????" + list.remove(2));
        System.out.println("??????" + list);
        // ?????????
        System.out.println("????2????7??" + list.set(2, 7));
        System.out.println("??????" + list);
        // ?????
        System.out.println("????1?3?????" + list.subList(1, 3));
        System.out.println("?????????" + list);
    }
}
      
     

????

?????[1, 2, 3]
???1??????[1, 4, 2, 3]
???3????2?????[1, 4, 2, 5, 6, 3]
??2????2
??5????4
??7????-1
????2????2
??????[1, 4, 5, 6, 3]
????2????7??[1, 7, 5, 6, 3]
????1?3?????[7, 5, 6]
?????????[1, 7, 5, 6, 3]

??

List???Java??????????????????????????????????????????????????????ArrayList?LinkedList????????????????????????????List????????????????Java??????????????