Java继承关系中构造器的使用详解

public class temp {
    public static void main(String[] args) {
//创建一个person对象，并初始化对象的name 和 age
        Person person = new Person("jack",18);
    }
}
class Person {
    String name;
    int age;
    //带有两个参数的构造器
    public Person(String name , int age){
        this.name = name;
        this.age =age;
    }
}

class Person {
    String name;
    int age;
    //显式声明无参构造器
    public Person(){
    }
    //带有两个参数的构造器
    public Person(String name , int age){
        this.name = name;
        this.age =age;
    }
}

//父类 Student
class Student {
    public String name;
    public int age;
    public double score;
   }
//子类 Pupil
class Pupil extends Student {
         //其拥有父类Student里面的所有属性
}
//子类Gratuate
class Gratuate extends Student{
         //其拥有父类Student里面的所有属性
}

//父类
class Base {
//显式声明一下无参构造器
    public Base() {
  System.out.println("父类Base中的构造器Base()被调用");
    }
}  
//子类
class Son extends Base {
    public Son() {
//显式声明一下无参构造器
System.out.println("子类Son的构造器Son()被调用");
  }
}
//主程序 
public class Run {
    public static void main(String[] args) {
        Son son = new Son();
    }
}Public 
   

class Son extends Base {
    public Son() {
   //编译不通过
        System.out.println("子类Son的构造器Son()被调用");
    }
}
class Base {
    public Base(int n1) {
    System.out.println("父类Base中的构造器Base(int n1)被调用");
    }
}

class Son extends Base {
    public Son() {
        super(2);//使用 Base(int n)构造器，传入一个int
        System.out.println("子类Son的构造器Son()被调用");
    }
class Base {
    public Base(int n1) {
    System.out.println("父类Base中的构造器Base(int n1)被调用");
    }