关于ArrayList的一些小的知识点的小程序

package cn.edu.hpu.hlj;


import java.util.ArrayList;


public class test {
public static void main(String[] args) {
ArrayList<String> list = new ArrayList<String>();
ArrayList<String> list1 = new ArrayList<String>();
ArrayList<ArrayList<String>> a = new ArrayList<ArrayList<String>>();
list.add("s");
list.add("h");
list.add("e");

System.out.println("list中的元素为："+list);
list.remove(0);
System.out.println(list.indexOf("h"));
System.out.println(list.get(0));
a.add(list);
list1.add("s1");
list1.add("h1");
list1.add("e1");
a.add(list1);
System.out.println(a.size());
System.out.println(a.get(0));
}


}