Collection ArrayList接口

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;

import javax.swing.text.html.HTMLDocument.Iterator;

public class Main {
	public static void main(String[] args) {
		Collection coll = new ArrayList();
		coll.add(1);
		coll.add("A");
		coll.add(2);
		//1.将集合coll2中的元素添加到集合coll中
		Collection coll2 = Arrays.asList(2, "B", 3);
		coll.addAll(coll2);
		System.out.println(coll);
		System.out.println(coll.contains("A"));
//		coll.clear();
		System.out.println(coll.size());
		System.out.println(coll.contains("A"));
		//2.判断coll是否包含coll2中所有元素
		System.out.println(coll);
		System.out.println(coll2);
		System.out.println(coll.containsAll(coll2));
		//3.coll和coll2交集
		coll.add(9);
		System.out.println(coll);
		System.out.println(coll2);
		coll.retainAll(coll2);
		System.out.println(coll);
		//4.删除coll中所有coll2中的元素
		coll.add(10);
		System.out.println(coll);
		System.out.println(coll2);
		coll.removeAll(coll2);
		System.out.println(coll);
		//5.哈希值
		Collection coll3 = new ArrayList();
		coll3.add("A");
		System.out.println(coll3.hashCode());
		//6.将集合转化为数组
		System.out.println(coll2);
		Object[] a = coll2.toArray();
		for (int i = 0; i < a.length; i++) {
			System.out.println(a[i]);
		}
		System.out.println();
	}
}