创建一个存储学生对象的集合，存储多个学生对象，使用程序实现在控制台遍历该集合 要求：学生对象的成员变量值相同，我们就认为是同一个对象

学生类(需要重写hashCode（）和equals（））

package package7;

import java.util.Objects;

public class Student {
    private String name;
    private int age;

    public Student() {
    }

    public Student(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        Student student = (Student) o;
        return age == student.age && Objects.equals(name, student.name);
    }

    @Override
    public int hashCode() {
        return Objects.hash(name, age);
    }
}

测试类

package package7;

import java.util.HashSet;

public class HashDemo2 {
    public static void main(String[] args) {
        //创建集合对象
        HashSet<Student> hs = new HashSet<>();
        //创建学生对象
        Student s1 =new Student("张三",21);
        Student s2 =new Student("李四",22);
        Student s3 =new Student("王五",23);
        Student s4 =new Student("王五",23);
        //把学生对象添加到集合中
        hs.add(s1);
        hs.add(s2);
        hs.add(s3);
        hs.add(s4);
        //遍历集合(增强for循环)
        for(Student s:hs){
            System.out.println(s.getName()+", "+s.getAge());
        }
    }
}