如何有多个对象的方法？

Question

我有一个程序，它有一个超级类，个人和子类，学生，并试图根据他们的生日和名字来比较他们什么时候是平等的。我做对了，但是在我试图解决的提示下，我得到了一个错误，自动评分器是：“测试学生和学生是一样的，即使成绩不同”，预期结果是真的，但我总是得到错误。这个程序在比较人和学生时起作用，在比较人和人时起作用，而不是学生和学生，我不知道为什么。

主要类别:

import java.util.Scanner;

public class PersonTester {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);

        System.out.println("Please enter the Person's name: ");
        String name = in.nextLine();
        System.out.println("Please enter the Person's birthday: ");
        String birthday = in.nextLine();

        System.out.println("Please enter the Student's name: ");
        String studentName = in.nextLine();
        System.out.println("Please enter the Student's birthday: ");
        String studentBirthday = in.nextLine();
        System.out.println("Please enter the Student's grade: ");
        int grade = in.nextInt();

        Person p1 = new Person(name, birthday);
        Student p2 = new Student(studentName, studentBirthday, grade);

        System.out.println("Same: " + p1.equals(p1, p2));
    }
}

超类:

public class Person {
    private String name;
    private String birthday;

    public Person(String name, String birthday) {
        this.name = name;
        this.birthday = birthday;
    }

    public String getBirthday() {
        return birthday;
    }

    public String getName() {
        return name;
    }

    //Create a equals method here
    public boolean equals(Person p1, Person p2) {
        boolean isEqual = false;
        if ((p1.getName()).equals(p2.getName()) 
                && (p1.getBirthday()).equals(p2.getBirthday())) {
            isEqual = true;
        }
        return isEqual;
    }
}

子类:

public class Student extends Person {
    //Instance variable
    private int grade;

    //Subclass constructor
    public Student(String name, String birthday, int grade) {
        super(name, birthday);
        this.grade = grade;
    }

    public int getGrade() {
        return grade;
    }
}

Answer 1

对人的实例 p1 使用等于 的方法。要编写正确的方法，请像这样编写此方法：

public boolean equals(Person p2) {
    boolean isEqual = false;
    if ((this.getName()).equals(p2.getName())
            && (this.getBirthday()).equals(p2.getBirthday())) {
        isEqual = true;
    }
    return isEqual;
}

当您调用此方法时，请执行以下操作:

p1.equals(p2)