学生信息管理系统V0.2（使用文件存储数据）【MVC模式、DAO模式、Factory模式】

0.2版更新内容：
1.使用文件存储数据；
2.使用HashMap查找学生信息；
3.使用DAO模式；
4.使用Factory模式；
5.使用BufferedReader、PrintWriter读写文件。

 

Student.java：学生类
程序代码 程序代码

package cn.edu.ahau.mgc.stu;

public class Student {

    private String id;
    private String name;
    private int age;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }
}



StudentAction.java：学生信息处理类
程序代码 程序代码

package cn.edu.ahau.mgc.stu;

import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Scanner;

public class StudentAction {

    Scanner sc = new Scanner(System.in);
    
    public void add() {
        Student stu = new Student();
        System.out.println("请输入学生学号：");
        String id = sc.next();
        System.out.println("请输入学生姓名：");
        String name = sc.next();
        System.out.println("请输入学生年龄：");
        int age = sc.nextInt();
        stu.setId(id);
        stu.setName(name);
        stu.setAge(age);
        try {
            DAOFactory.getStudentDAOInstance().add(stu);
        } catch (Exception e) {
            System.out.println("添加学生信息失败！");
        }
    }
    
    public void showAll() {
        List<Student> stus = null;
        try {
            stus = DAOFactory.getStudentDAOInstance().queryAll();
        } catch (Exception e) {
            System.out.println("信息查找失败！");
        }
        Iterator<Student> iter = stus.iterator();
        this.printHeader();
        while (iter.hasNext()) {
            Student stu = iter.next();
            this.print(stu);
        }
        this.printFooter();
    }
    
    public void printHeader() {
        System.out.println("------------------------");
        System.out.println("学号\t姓名\t年龄");
        System.out.println("------------------------");
    }
    
    public void printFooter() {
        System.out.println("------------------------");
    }
    
    public void print(Student stu) {
        System.out.println(stu.getId() + "\t" + stu.getName() + "\t" + stu.getAge());
    }
    
    public Student queryById() {
        System.out.println("请输入学号：");
        String id = sc.next();
        HashMap<String, Student> stus = null;
        try {
            stus = DAOFactory.getStudentDAOInstance().queryById();
        } catch (Exception e) {
            System.out.println("信息查找失败！");
        }
        Student stu = null;
        if (stus.containsKey(id)) {
            stu = stus.get(id);
        }
        if (stu != null) {
            this.printHeader();
            this.print(stu);
            this.printFooter();
        } else {
            System.out.println("对不起，没找到您要查找的学生！");
        }
        return stu;
    }
    
}



DAOFactory.java：数据操作工厂类
程序代码 程序代码

package cn.edu.ahau.mgc.stu;

public class DAOFactory {

    public static StudentDAO getStudentDAOInstance() {
        return new StudentDAOImpl();
        
    }
}



StudentDAO.java：学生信息数据操作接口
程序代码 程序代码

package cn.edu.ahau.mgc.stu;

import java.util.HashMap;
import java.util.List;


public interface StudentDAO {

    //查询所有学生信息
    public List<Student> queryAll() throws Exception;
    //按ID查询学生信息
    public HashMap<String, Student> queryById() throws Exception;
    //添加学生信息
    public void add(Student stu) throws Exception;
    
}



StudentDAOImpl.java：学生信息数据操作实现类
程序代码 程序代码

package cn.edu.ahau.mgc.stu;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;

public class StudentDAOImpl implements StudentDAO {

    public static final String FILE_PATH = "DB/student.txt";
    
    public List<Student> queryAll() throws Exception {
        List<Student> stus = new ArrayList<Student>();
        FileReader fr = null;
        BufferedReader br = null;
        try {
            fr = new FileReader(FILE_PATH);
            br = new BufferedReader(fr);
            String stuStr = null;
            while ((stuStr = br.readLine()) != null) {
                String[] stuMsg = stuStr.split(":");
                if (stuMsg.length == 3) {
                    Student stu = new Student();
                    stu.setId(stuMsg[0]);
                    stu.setName(stuMsg[1]);
                    int age = 20;
                    try {
                        age = Integer.parseInt(stuMsg[2]);
                    } catch (NumberFormatException e) {
                        age = 20;
                    }
                    stu.setAge(age);
                    stus.add(stu);
                }
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            throw new Exception(e);
        } catch (IOException e) {
            e.printStackTrace();
            throw new Exception(e);
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (Exception e) {
                    e.printStackTrace();
                    throw new Exception(e);
                }
                br = null;
            }
            if (fr != null) {
                try {
                    fr.close();
                } catch (Exception e) {
                    e.printStackTrace();
                    throw new Exception(e);
                }
                fr = null;
            }
        }
        return stus;
    }
    
    public HashMap<String, Student> queryById() throws Exception {
        HashMap<String, Student> stus = new HashMap<String, Student>();
        FileReader fr = null;
        BufferedReader br = null;
        try {
            fr = new FileReader(FILE_PATH);
            br = new BufferedReader(fr);
            String stuStr = null;
            while ((stuStr = br.readLine()) != null) {
                String[] stuMsg = stuStr.split(":");
                if (stuMsg.length == 3) {
                    Student stu = new Student();
                    stu.setId(stuMsg[0]);
                    stu.setName(stuMsg[1]);
                    int age = 20;
                    try {
                        age = Integer.parseInt(stuMsg[2]);
                    } catch (NumberFormatException e) {
                        age = 20;
                    }
                    stu.setAge(age);
                    stus.put(stuMsg[0], stu);
                }
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            throw new Exception(e);
        } catch (IOException e) {
            e.printStackTrace();
            throw new Exception(e);
        } finally {
            if (br != null) {
                try {
                    br.close();
                } catch (Exception e) {
                    e.printStackTrace();
                    throw new Exception(e);
                }
                br = null;
            }
            if (fr != null) {
                try {
                    fr.close();
                } catch (Exception e) {
                    e.printStackTrace();
                    throw new Exception(e);
                }
                fr = null;
            }
        }
        return stus;
    }

    public void add(Student stu) throws Exception {
        FileWriter fw = null;
        PrintWriter pw = null;
        try {
            fw = new FileWriter(FILE_PATH, true);
            pw = new PrintWriter(fw, true);
            pw.println(stu.getId() + ":" + stu.getName() + ":" + stu.getAge());
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (pw != null) {
                pw.close();
                pw = null;
            }
            if (fw != null) {
                try {
                    fw.close();
                } catch (IOException e) {
                    e.printStackTrace();
                    throw new Exception(e);
                }
                fw = null;
            }
        }
    }

}



StudentMgr.java：学生信息管理类
程序代码 程序代码

package cn.edu.ahau.mgc.stu;

import java.util.Scanner;

public class StudentMgr {

    
    
    public static void main(String[] args) {
        StudentAction sa = new StudentAction();
        Scanner sc = new Scanner(System.in);
        boolean flag = true;
        while (flag) {
            showMenu();
            int selected = sc.nextInt();
            switch(selected) {
            case 1 :
                sa.add();
                break;
            case 2 :
                sa.showAll();
                break;
            case 3 :
                sa.queryById();
                break;
            case 4 :
                flag = false;
                System.out.println("已退出！");
                break;
            }
        }
    }
    
    public static void showMenu() {
        System.out.println("学生信息管理菜单：");
        System.out.println("（1）增加学生信息");
        System.out.println("（2）显示所有学生信息");
        System.out.println("（3）根据学号查询学生信息");
        System.out.println("（4）退出管理");
    }
    
}



student.txt：学生数据文件
程序代码 程序代码

1001:Magci:20
1002:MGC:20
1003:haha:24
1005:lala:19
1004:test:23