Java-18，继承中的构造方法

class SuperClass {
    private int n;
      
      /*
    SuperClass() {
        System.out.println("SuperClass()");
    }
    */
    
  
    SuperClass(int n) {
        System.out.println("SuperClass(" + n + ")");
        this.n = n;
    }
}

class SubClass extends SuperClass {
    private int n;
    
    SubClass(int n) {
            //super();
        System.out.println("SubClass(" + n + ")");
        this.n = n;
    }
    
    SubClass() {
            super(300);
        System.out.println("SubClass()");
    }
}

public class TestSuperSub {
    public static void main(String arg[]) {
        //SubClass sc1 = new SubClass();
        SubClass sc2 = new SubClass(400);
    }
}