a extends b java_(class B extends A) 怎么解释?A是上一个类名
哦,多谢!是类的继承。源码:class StudentTest{public static void main(String[] args){Student aStudent = new Student();aStudent.setName("张楠");aStudent.setStudentNum("20030408");System.out.println("学生的姓名是:" + aStuden...