JAVA高级教程-Java ArrayList(3)

4、ArrayList的使用

package ArrayList01;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.ListIterator;

public class day05 {

    public static void main(String[] args) {
        //创建集合
        ArrayList arrayList =new ArrayList<>();

        //添加元素
        Student s1= new Student("张三",18);
        Student s2= new Student("李四",20);
        Student s3= new Student("王五",25);
        arrayList.add(s1);
        arrayList.add(s2);
        arrayList.add(s3);

        //删除元素
        arrayList.remove(s1);
        arrayList.remove(new Student("李四",20));
        System.out.println("删除后的元素"+arrayList.size());
        System.out.println(arrayList.toString());

        //遍元素
        //遍历元素
        System.out.println("===============for循环===============");
        for(int i=0;i<arrayList.size();i++){
            System.out.println(arrayList.get(i));
        }


        System.out.println("============增强for循环===============");
        for(Object obj:arrayList){
            System.out.println(obj);
        }

        System.out.println("============使用迭代器===============");
        Iterator it=arrayList.iterator();
        while (it.hasNext()){
            //不能使用Collection删除
            System.out.println(it.next());
        }

        System.out.println("============使用列表迭代器===============");
        ListIterator it1=arrayList.listIterator();
        while (it1.hasNext()){
            //不能使用Collection删除
            System.out.println(it1.next());
        }

        //查询
    }

}
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