学生成绩管理系统(java语言)

学生成绩管理系统
import java.util.*;
import java.io.*;
class Student implements Serializable {
String name;
long no;
private String[] course={"os","java","math"};
double[] cscore={0,0,0};
public Student(String name,long no,double a,double b,double c){
=name;
this.no=no;
this.cscore[0]=a;
this.cscore[1]=b;
this.cscore[2]=c;
}
@Override public String toString(){
return +" "+this.no+" "+this.course[0]+":"+this.cscore[0]
+" "+this.course[1]+":"+this.cscore[1]+" "+this.course[2]+":"+this.cscore[2];
}
}
public class Object{
private static Scanner scanner=new Scanner(System.in);
public Student[] read()throws Exception{
ObjectInputStream objIn=new ObjectInputStream(new FileInputStream("stus.data"));
int num=objIn.readInt();
Student[] stus=new Student[num];
for(int i=0;i<num;i++){
stus[i]=(Student)objIn.readObject();
}
objIn.close();
return stus;
}
public void add(Student[] stus)throws Exception{
Student[] s=new Student[stus.length+1];
for(int i=0;i<s.length-1;i++){s[i]=stus[i];}
System.out.print("请输入要添加的学生信息：\n"+"姓名：");String name=scanner.next();
System.out.print("学号：");long no=scanner.nextInt();
System.out.print("os成绩：");double cscore0=scanner.nextDouble();
System.out.print("java成绩：");double cscore1=scanner.nextDouble();
System.out.print("math成绩：");double cscore2=scanner.nextDouble();
s[s.length-1]=new Student(name,no,cscore0,cscore1,cscore2);save(s);
System.out.println("添加成功！");
}
public void dispAll(Student[] stus){
System.out.println("现有Student信息为：");
for(Student stu:stus){
System.out.println(stu);
}
}
public void save(Student[] stus)throws Exception{
ObjectOutputStream objOut=new ObjectOutputStream(new FileOutputStream("stus.data"));
objOut.writeInt(stus.length);
for(Student stu:stus){
objOut.writeObject(stu);
}
objOut.close();
}
public void findById(Student[] stus){
int no=0,i=0;
System.out.print("请输入学号：");no=scanner.nextInt();
for(i=0;i<stus.length;i++){
if(stus[i].no==no){System.out.println(stus[i]);break;}
if(stus[i].no!=no&&i==stus.length-1){System.out.println("无该生信息！");} }
}
public void findByName(Student[] stus){
String name="";
System.out.print("请输入姓名：");name=scanner.next();
for(int i=0;i<stus.length;i++){
if(name.equalsIgnoreCase(stus[i].name)==true){System.out.println(stus[i]);break;}
if(name.equalsIgnoreCase(stus[i].name)==false&&i==stus.length-1){System.out.println("无该生信息！");}
}
}
public void delById(Student[] stus)throws Exception{
int no=0,i=0;
System.out.print("请输入学号：");no=scanner.nextInt();
for(i=0;i<stus.length;i++){
if(stus[i].no==no){System.out.println(stus[i]);stus[i]=null;save(stus);System.out.println("删除成功！");break;}
if(stus[i].no!=no&&i==stus.length-1){System.out.println("无该生信息！");} }
}
public static void main(String[] args)throws Exception{
Object demo=new Object();
Student[] stus={new Student("zhang",1,90,90,98),new Student("wang",2,80,80,89),new Student("li",3,70,70,79)};
System.out.print("请输入操作的编号：");System.out.print("\n");
int choice=0;
do{
System.out.println("1 添加 2 显示所有学生信息 3 按学号查找 4 按姓名查找 5 按学号删除 6 保存0 退出");
choice=scanner.nextInt();
switch(choice){
case 1: demo.add(demo.read());break;
case 2: demo.dispAll(demo.read());break;
case 3: demo.findById(demo.read());break;
case 4: demo.findByName(demo.read());break;
case 5: demo.delById(demo.read());break;
case 6: demo.save(stus);break;
case 0: break;
default: System.out.println("Error!");
}
}while(choice!=0);
}
}。