java基础案例4-4学生和老师

package com.itheima; import java.util.Scanner;  abstract class Person{     void speak(){} }  class Teacher extends Person{     private String name;     void setName(String name){         this.name = name;     }     String getName(){         return name;     }     void speak(){         System.out.println("如何写这个问题？");     } }  class Student extends Person{     private String name;     void setName(String name)     {         this.name = name;     }     String getName(){         return name;     }     void speak(){         System.out.println("不会");     } }  public class Main{     public static void main(String[] args)     {         Teacher teacher = new Teacher();         Student student = new Student();         teacher.setName("老王");         Scanner in = new Scanner(System.in);         String choose = in.next();         student.setName(choose);         System.out.println(teacher.getName()   "向" student.getName() "提问");         System.out.print(teacher.getName() "说：");         teacher.speak();         System.out.print(student.getName() "说：");         student.speak();     } }