# 範例 ```java= public class GetDBNew extends GetDB { // 要加入的新屬性 private String num; private String age; public GetDBNew(int id, String num, String name, String age, String email) { super(id, name, email);// 父類別的內容 this.num = num; this.age = age; } public String getDB() { return num + age; } } ``` ```java= public class GetDB { // 設置屬性 private int id; private String name; private String email; // 初始化 public GetDB(int id, String name, String email) { super(); this.id = id; this.name = name; this.email = email; } // 建構子 public String getDB() { return id + name + email; } } ``` ```java= public class MyGetDB { public static void main(String[] args) { GetDB db= new GetDB(1, "Tim", "t@mail.coms"); GetDBNew dbn =new GetDBNew(2, "30", "Yam", "25", "y@mail.com"); } } ```