Ailt + Insert 选择 equals() 和 hashCode()

package com.zhong.collection.set;

import java.util.HashSet;
import java.util.Objects;

public class HashSetDeduplication {
    public static void main(String[] args) {
        // HashSet 对象去重
        HashSet<Student> students = new HashSet<>();
        students.add(new Student("小钟", 22));
        students.add(new Student("小钟", 22));
        students.add(new Student("小王", 21));
        students.add(new Student("张三", 60));
        students.add(new Student("张三", 80));
        for (Student student : students) {
            System.out.println(student);
        }
    }

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

    // 重写 equals 和 hashCode

    @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);
    }

    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 String toString() {
        return "Student{" +
                "name='" + name + '\'' +
                ", age=" + age +
                '}';
    }
}