java接口与继承

class Grandparent {

 public Grandparent() {        System.out.println("GrandParent Created.");    }

    public Grandparent(String string) {        System.out.println("GrandParent Created.String:" + string);    }}

class Parent extends Grandparent {

    public Parent() {        //super("Hello.Grandparent.");        System.out.println("Parent Created");       // super("Hello.Grandparent.");    }}

class Child extends Parent {

    public Child() {        System.out.println("Child Created");    }}

public class TestInherits {

    public static void main(String args[]) {        Child c = new Child();    }}public为共有类，子继承父母，父母继承祖父母通过 super 调用基类构造方法，必须是子类构造方法中的第一个语句。