序列化与反序列化

package 学生管理系统;

import java.io.*;
import java.util.Arrays;
import java.util.Comparator; 
import java.util.ArrayList;
import java.util.Scanner;

class Student implements Serializable{
    public int num;
    public String name,sex,obj;
    
    Student()
    {
        this.num = 0;
        this.name = "";
        this.sex = "";
        this.obj = "";
    }
    
    Student(int _num  ,String _name,String _sex,String _obj){
        this.num = _num;
        this.name = _name;
        this.sex = _sex;
        this.obj = _obj;    
    }
    
    void print(){
        System.out.println("学号:"+num+"     姓名:"+name+"     性别:"+sex+"     专业:"+obj);
    }
    
}

public class StudentMIS {

    /**
     * @param args
     */
    
    //保存  序列化
    public static void save(ArrayList<Student> student){
        try{
            ObjectOutputStream os = new ObjectOutputStream(
                    new FileOutputStream("F:\\输入输出\\student.dat"));
            
            os.writeObject(student);
            os.close();
            System.out.println("写入成功.");
        }
        catch (Exception e){
            System.out.println("发生异常"+e);
            e.printStackTrace();
        }

    }
    
    //显示 反序列化
    public static ArrayList<Student> read(){
        File f = new File("F:\\输入输出\\student.dat");
        if(f.exists()){    
            try{
                ObjectInputStream ois = new ObjectInputStream(new FileInputStream(f));
    
                ArrayList<Student> student = (ArrayList<Student>)ois.readObject();
                            
                ois.close();
                
                System.out.println("读取成功.");
                return student;
            }
            catch(IOException e){
                System.out.println("发生异常1"+e);
                e.printStackTrace();
            }
            catch(ClassNotFoundException e){
                System.out.println("发生异常2"+e);
                e.printStackTrace();
            }
            
        }    
        
        return null;
    }
    
    
    public static void main(String[] args){
            ArrayList<Student> student = new ArrayList<Student>(0);
            student = read();//反序列化
    
            int choose = 0;
            
            int num;
            String name,sex,obj;
            
            Scanner in = new Scanner(System.in);        
            do{
                System.out.println("1.增加        2.删除        3.显示        4.修改        5.保存        6.退出");
                choose = in.nextInt();
                switch(choose){
                case 1:
                    Student temp = new Student();
                    System.out.println("请输入学号:");
                    temp.num = in.nextInt();
                    System.out.println("请输入姓名:");
                    temp.name = in.next();
                    System.out.println("请输入性别:");
                    temp.sex = in.next();
                    System.out.println("请输入专业:");
                    temp.obj = in.next();
                    
                    
                    student.add(temp);        
                    break;
                    
                case 2:
                    System.out.print("请输入你要删除的学号");
                    num = in.nextInt();
                    for(int i=0;i<student.size();i++){
                        if(student.get(i).num == num){
                            student.remove(i);
                        }
                    }
                    break;
                    
                case 3:
                    for(int i=0;i<student.size();i++){
                        student.get(i).print();
                    }
                    break;
                    
                case 4:
                    System.out.print("请输入你要修改的学生学号");
                    num = in.nextInt();
                    int i;
                    for(i=0;i<student.size();i++){
                        if(student.get(i).num == num){
                            System.out.println("请输入新的学号:");
                            student.get(i).num = in.nextInt();
                            System.out.println("请输入姓名:");
                            student.get(i).name = in.next();
                            System.out.println("请输入性别:");
                            student.get(i).sex = in.next();
                            System.out.println("请输入专业:");
                            student.get(i).obj = in.next();
                            
                            System.out.println("修改成功.");
                        }
                    }
                    
                    if(i == student.size()){
                        System.out.println("无该学生!");
                    }
                    break;
                    
                    
                case 5:
                    save(student);
                    break;
                
                case 6:
                    choose = 7;
                    break;
                }
            }while(choose >= 1 && choose <= 6 );
    }
}