集合基础练习

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

//集合练习
public class Collection83 {
    public static void main(String[] args) {
        Collection coll=new ArrayList();
        //1.add()方法
        coll.add("DD");
        coll.add("MM");
        coll.add(789);
        coll.add(new Date());
        System.out.println(coll);
        System.out.println("*****************************************");
        //2.size()方法
        System.out.println(coll.size());
        Collection coll2=new ArrayList();
        coll2.add("CC");
        coll2.add("WW");
        coll.addAll(coll2);
        System.out.println(coll);
        System.out.println(coll.size());
        System.out.println("*******************************88888888");
        //4.isEmpty()
        System.out.println("*******************************");
        System.out.println(coll.isEmpty());
        //*************************************************
        //clear()
        coll2.clear();
        System.out.println(coll2);
        System.out.println(coll);
        System.out.println(coll.size());
        //6.contains()方法
        coll.add(new String("小兰"));
        coll.add(false);
        System.out.println(coll);
        //********************************************
        System.out.println(coll.contains(new String("小兰")));
        Person p=new Person("小红",20);
        coll.add(p);
        System.out.println(coll);
        System.out.println(coll.contains(p));
        boolean b=coll.contains(p);
        System.out.println("*******************************");
        System.out.println(b);
        System.out.println("********************************8");
        coll.add(new Person("小红",20));
        System.out.println(coll);
        System.out.println(new Person("小红",20));
        System.out.println(coll.contains(p));
    }
}
class Person{
    private String name;
    private int age;
    public Person(){}
    public Person(String name,int age){
        this.name=name;
        this.age=age;
    }

}