public class Person {
private String name;
private int age;
public Person() {
}
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public void gomethod() {
System.out.println("欢迎来到北京!北京欢迎你!");
}
}
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
/**
*
* 2021.11.7
* 集合强化练习
*/
public class Colection84 {
public static void main(String[] args) {
//创建集合,并添加元素
Collection coll=new ArrayList();
coll.add(new Date());
System.out.println(coll);
coll.add("MM");
coll.add(896);//包装类
coll.add(new String("魅力四射"));
System.out.println(coll);
Collection colle=new ArrayList();
colle.add("希望的田野");
coll.addAll(colle);
System.out.println(coll);
System.out.println(colle.isEmpty());
colle.clear();
System.out.println(colle);
System.out.println("***************************************");
System.out.println(coll.size());
System.out.println(coll.getClass());
System.out.println(coll.contains(896));
System.out.println("***************************************");
Person p=new Person("小红",20);
coll.add(p);
System.out.println(coll);
System.out.println(coll.contains(p));
}
}