student.java

Java课堂练习

/**
 * @(#)CloneExp.java
 *
 *
 * @author 
 * @version 1.00 2007/11/17
 */
import java.io.*;
class Grade implements Serializable {
 double  chinese_grd;
 double  math_grd;
 double  english_grd;
 Grade(double a,double b,double c) {
  chinese_grd=a;  math_grd=b;  english_grd=c;
 }
 double  SumGrd() {
  return  (chinese_grd+math_grd+english_grd);
 }
 double  AvgGrd() {
  return  (SumGrd()/3);
 }
}
 
public class  Student implements Cloneable,Serializable {
 String name;
 int age;
 char sex;
 Grade grade;
 Student (String s,int a,char x,Grade g) {
  name=s; age=a;  sex=x;  grade=g;
 }
 void output() {
 System.out.println("name="+name+"age="+age+"sex="+(sex=='M'?"男":"女"));
 System.out.println("Chinese Grade="+grade.chinese_grd+"Math Grade="+grade.math_grd+"English Grade="+grade.english_grd);
 System.out.println("the sum of grade="+grade.SumGrd()+"the average of grade="+grade.AvgGrd());
 }
 /* protected   Object  clone() {
  System.out.println("this is deep clone method!");
  Student std;
  String s=new String(this.name);
  int a=this.age;
  char x=this.sex;
  Grade g=new Grade(this.grade.chinese_grd,this.grade.math_grd,this.grade.english_grd);
  std=new Student(s,a,x,g);
  return std;  
 } */	
 public static void main(String[] args) {
        // TODO code application logic here
      Grade  g=new Grade(70,80,90);
      Student  s1=new Student("王明",31,'M',g);
      Student s2=s1;
      Student s3;
      try {
       s3=(Student)(s1.clone());
       s3.grade.english_grd=98;
      }
      catch (Exception e) {
       System.out.println(e);
      }      
      s1.output();
    }
}