date0407/DuotaiDemo3.java

/*基础班学生：学习(不确定)，睡觉(坐着睡)。高级班学生：学习(不确定)，睡觉(躺着睡)。冲刺班学生:学习(不确定)，睡觉(躺着睡)。可以将这三类事物进行抽取。分析：1、都学习，但学习内容不确定，就在父类中定义成抽象的。2、都睡觉，睡觉多数（2：1）是躺着睡，那么在父类中的函数就定义出函数主体，内容为躺着睡，子类直接去继承，少数要坐着睡，那就让它去重写成坐着睡。*/abstract class Student{public abstract void study();public void sleep(){System.out.println("躺着睡");}}class BaseStudent extends Student{public void study(){System.out.println("base study");}public void sleep(){System.out.println("坐着睡");}}class AdvStudent extends Student{public void study(){System.out.println("adv study");}}class ChongciStudent extends Student{public void study(){System.out.println("chongci study");}}class StudentDo{public static void DoSomething(Student s){s.study();s.sleep();}}class DuotaiDemo3 {public static void main(String[] args) {/*BaseStudent st = new BaseStudent();st.study();st.sleep();AdvStudent at = new AdvStudent();at.study();at.sleep();ChongciStudent ct = new ChongciStudent();ct.study();ct.sleep();*/StudentDo sd = new StudentDo();//类创建对象，对象调用函数。sd.DoSomething(new BaseStudent());sd.DoSomething(new AdvStudent());sd.DoSomething(new ChongciStudent());}}