JAVA Set接口

import org.junit.Test;

import java.util.HashSet;
import java.util.LinkedHashSet;
import java.util.Set;
import java.util.TreeSet;

public class TestSet {
    /*
        Collection接口：
        |---Set接口：存储无序，不可重复的元素
            1，HashSet
            2,LinkedHashSet
            3,TreeSet
            Set的元素是如何保存的：使用了哈希算法
            向Set中添加对象时：调用hashCode()方法，计算哈希值
            hashCode()方法要与equals()方法一致

     */
    @Test
    public void testTreeSet1(){
        Set set =new TreeSet();

    }
    @Test
    public void testLinkedHashSet(){
        Set set =new LinkedHashSet();
        set.add(123);
        set.add("aaa");

    }
    @Test
    public void testHashSet() {
            //Set无序性：无序性！=随机性
            //不可重复
            Set set = new HashSet();
            set.add(123);
            set.add("abd");
            Person p1 =new Person("noo",18);
            Person p2 =new Person("noo",18);
            System.out.println(p1.equals(p2));
            System.out.println(p1.hashCode());
            System.out.println(p2.hashCode());
            System.out.println(set.size());
            set.add(p1);
            set.add(p2);
            System.out.println(set);
    }


}

public class Person {
    private String name ;
    private Integer age ;
    public String getName(){
        return name;
    }
    public Integer getAge(){
        return age;
    }
    public void setName(){
        this.name=name;
    }
    public void setAge(){
        this.age=age;
    }
    public Person(String name,Integer age){
        super();
        this.age=age;
        this.name=name;
    }
    public Person(){
        super();
    }
    @Override
    public String toString(){
        return "Person[name="+name+",age="+age+"]";
    }
}