11.断点追踪初始化过程

class Person {
    String name="李光";// 姓名
    public Person() {
        // super();//写不写该语句，效果一样
        System.out.println("execute Person()");
    }
    public Person(String name) {
        this.name = name;
        System.out.println("execute Person(name)");
    }
}

class Student extends Person {
    String school="武汉大学";// 学校
    public Student() {
        // super();//写不写该语句，效果一样
        System.out.println("execute Student() ");
    }
    public Student(String name, String school) {
        super(name); // 显示调用了父类有参构造方法，将不执行无参构造方法
        this.school = school;
        System.out.println("execute Student(name,school)");
    }
}

class PostGraduate extends Student {
    String guide;// 导师
    public PostGraduate() {
        // super();//写不写该语句，效果一样
        System.out.println("execute PostGraduate()");
    }
    public PostGraduate(String name, String school, String guide) {
        super(name, school);
        this.guide = guide;
        System.out.println("execute PostGraduate(name, school, guide)");
    }
}

class TestInherit {
    public static void main(String[] args) {
        PostGraduate pgdt=null;
        pgdt = new PostGraduate();
        System.out.println();
        pgdt=new PostGraduate("刘致同","北京大学","王老师");
    }
}