JAVA类继承机制代码

 1 class Parent {
 2     private int num = 1;
 3     public Parent() {
 4         System.out.println("Now,initial parent calss.");
 5     }
 6     public void test() {
 7         System.out.println("This is the parent's test method.");
 8     }
 9 }
10 
11 public class ParentTest extends Parent {
12     private String name;
13     private int age;
14     public ParentTest() {
15         name = "Sky";
16         age = 20;
17     }
18     public static void main(String[] args) {
19         ParentTest t = new ParentTest();
20         t.test();
21         System.out.println(t.name + "'s age is :" + t.age);
22     }
23 }