(1)增加
public class TestCollection {
public static void main(String[] args) {
ArrayList hero=new ArrayList();
for (int i = 0; i < 5; i++) {
hero.add(new Hero("hero"+i));
}
System.out.println(hero);
Hero hero2=new Hero("s");
hero.add(3,hero2);
System.out.println(hero.toString());
}
}
public class Hero {
public String name;
public float hp;
public int damage;
public Hero(){
}
public Hero(String name){
this.name=name;
}
public String toString(){
return name;
}
}
(2)判断是否存在
System.out.println(hero.contains(new Hero("hero 1")));
System.out.println(hero.contains(hero2));
(3)获取制定位置的对象
//获得制定位置的对象
System.out.println(hero.get(5));
//如果超出范围,依然会报错
System.out.println(hero.get(6));
(4)删除
hero.remove(2);
System.out.println(hero);
(5)获得对象所处的位置
indexOf用于判断一个对象在ArrayList中所处的位置
与containsyiyang,判断标准是对象是否相同,而非对象的name值是否相等
System.out.println(hero.indexOf(new Hero("hero 1")));
System.out.println(hero.indexOf(hero2);
(6)替换
hero.set(5,new Hero("hero 5"));
System.out.println(hero);
(7)获取大小
System.out.println(hero.size());
(8)转换为数组
Hero hs[]=(Hero[])hero.toArray(new Hero[]{}};
System.out.println(hs);
(9)把另一个容器所有对象都加进来
ArrayList ay=new ArrayList();
ay.add(new Hero("hero a"));
ay.add(new Hero("hero b"));
System.out.println(ay);
hero.addAll(ay);
System.out.println(hero);
(10)清空
hero.clear();
System.out.println(hero);