Java继承实例：Person类与CollegeGraduate类详解

import java.time.Year;

class Person {
    private String name;
    private int birthYear;

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

    public String getName() {
        return name;
    }

    public int getAge() {
        int currentYear = Year.now().getValue();
        return currentYear - birthYear;
    }
}

class CollegeGraduate extends Person {
    private double gpa;
    private int graduateYear;

    public CollegeGraduate(String name, int birthYear, double gpa, int graduateYear) {
        super(name, birthYear);
        this.gpa = gpa;
        this.graduateYear = graduateYear;
    }

    public double getGpa() {
        return gpa;
    }

    public int getGraduateYear() {
        return graduateYear;
    }
}

public class PersonTest {
    public static void main(String[] args) {
        CollegeGraduate graduate = new CollegeGraduate('John Smith', 1990, 3.8, 2022);
        System.out.println('Name: ' + graduate.getName());
        System.out.println('Age: ' + graduate.getAge());
        System.out.println('Graduate Year: ' + graduate.getGraduateYear());
        System.out.println('GPA: ' + graduate.getGpa());
    }
}