public class test { public static void main(String[] args) { Student stu1 =new Student("学炜",24); stu1.show(); Student stu2=new Undergradute("学炜",24,"硕士"); stu2.show(); } } public class Student {          String name;     int age;              public Student() {         super();     }     public Student(String name, int age) {         super();         this.name = name;         this.age = age;     }          public void show(){                 System.out.println("学生的名字为："+this.name+" 学生的年龄为："+this.age);     }          } public class Undergradute extends Student{     private  String degree;//学位     public Undergradute() {         super();             }     public Undergradute(String name, int age,String degree) {         super(name, age);         this.degree=degree;     }          public void show(){         System.out.println("学生的名字为："+this.name+" 学生的年龄为："+this.age+" 学生的专业为："+this.degree);     }           }