【CollectionDemo1】

package com.yjf.esupplier.common.test;

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

/**
 * @author shusheng
 * @description Collection接口成员方法
 * @Email shusheng@yiji.com
 * @date 2018/12/11 16:21
 */
public class CollectionDemo1 {

    public static void main(String[] args) {

        Collection c = new ArrayList();
        ((ArrayList) c).add("hello");
        ((ArrayList) c).add("world");
        ((ArrayList) c).add("java");

        System.out.println("size:"+c.size());

        System.out.println("c:" + c);

        System.out.println("remove:" + c.remove("hello"));
        System.out.println("remove:" + c.remove("hello"));

        System.out.println("contains:" + c.contains("world"));
        System.out.println("contains:" + c.contains("android"));
        System.out.println("isEmpty:"+c.isEmpty());
        c.clear();
        System.out.println("isEmpty:"+c.isEmpty());
    }

}

执行结果：

size:3
c:[hello, world, java]
remove:true
remove:false
contains:true
contains:false
isEmpty:false
isEmpty:true