java基础入门-iterator迭代器与集合下标的使用

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

public class Test {

	public Test() {
		// 初始化List
		addItemToList();
	}

	private ArrayList<String> list = new ArrayList<String>();

	private void addItemToList() {
		for (int i = 0; i < 5; i++) {
			list.add(i + "");
		}
	}

	public ArrayList<String> getList() {
		return list;
	}

	public void setList(ArrayList<String> list) {
		this.list = list;
	}

	public static void main(String[] args) {
		Test test1 = new Test();
		ArrayList<String> test1List = test1.getList();
		for (int i = 0; i < test1List.size(); i++) {
			// 这里使用下标，直接指向元素
			test1List.remove(i);
		}
		System.out.println("test1List have been removed all elements");
		Test test2 = new Test();
		ArrayList<String> test21List = test2.getList();
		for (Iterator<String> iterator = test21List.iterator(); iterator
				.hasNext();) {
			// 使用迭代器对集合操作时,需要先做next()
			// next()类似于游标，他是介于两个元素之间的
			// 不像上面直接指向某个元素
			iterator.next();
			iterator.remove();
		}
		System.out.println("test2List have been removed all elements");
	}
}