- package com.company.section3;
- /**
- * @author cbf4Life cbf4life@126.com
- * I'm glad to share my knowledge with you all.
- */
- public abstract class Element {
- //定义业务逻辑
- public abstract void doSomething();
- //允许谁来访问
- public abstract void accept(IVisitor visitor);
- }