Java项目中不想有数据库密码 不用数据库的java管理系统

1. Subject

 

public class Subject{
    private String name;//学科名称
    private String number;
    public Subject() {}
    
    public Subject(String name, String number) {
        this.name = name;
        this.number = number;
        
    }

    public String getName() {
        return name;
    }

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

    public String getNumber() {
        return number;
    }

    public void setNumber(String number) {
        this.number = number;
    }

}

2.Student

import java.util.Scanner;


public class Student {
    private String name;//姓名
    private String ID;//学号
    private double grade;//成绩
    private Subject subject;//学科（学科内容、学科编号）
    Scanner sc = new Scanner(System.in);
    public Student() {}
    
    public  Student(String ID, String name, double grade, Subject subject) {
        this.ID = ID;
        this.name = name;
        this.grade = grade;
        this.subject = subject;
    }
    
    public String getName() {
        return name;
    }

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

    public String getID() {
        return ID;
    }

    public void setID(String iD) {
        ID = iD;
    }

    public double getGrade() {
        return grade;
    }

    public void setGrade(double grade) {
        this.grade = grade;
    }

    public Subject getSubject() {
        return subject;
    }

    public void setSubject(Subject subject) {
        this.subject = subject;
    }

    public Scanner getSc() {
        return sc;
    }

    public void setSc(Scanner sc) {
        this.sc = sc;
    }

    //输入学生信息方法
    public void scc() {
         System.out.print("请输入学生的姓名：");
         String name = sc.next();
         
         System.out.print("请输入学生的学号：");
         
         String ID = sc.next();
         System.out.print("请输入学生的成绩：");
     
         double grade = sc.nextInt();
         System.out.print("请输入学生的学科：");
         String subject = sc.next();
         System.out.print("请输入学生的学科编号：");
         String number = sc.next();
         
         new Student(ID, name, grade, new Subject(subject, number));
         System.out.println("添加成功！！！！！");
    }

}

3.Main

import java.util.List;
import java.util.ArrayList;
import java.util.Scanner;


public class Main {
    static Scanner sc = new Scanner(System.in);
    public static void main(String[] args) {

        List<Student> list = new ArrayList();
//        list.add(scc());
        System.out.println(list.get(0).getID());
        
        
        
    }
    
    
    
    //界面函数
    public void infa() {
        System.out.println("欢迎光临学生信息管理系统");
        System.out.println("请选择功能");
        System.out.println("1、添加学生信息");
        System.out.println("2、获得指定学生成绩");
        System.out.println("3、获得指定学号的成绩");
        System.out.println("4、根据学生ID修改姓名");
        System.out.println("5、根据姓名修改指定学科成绩");
        System.out.println("6、删除指定学生及成绩");
        System.out.println("0、退出");
    }
    
    //创建学生对象
    public Student create() {
         System.out.print("请输入学生的姓名：");
            String name = sc.next();
            System.out.print("请输入学生的学号：");        
            String ID = sc.next();
            System.out.print("请输入学生的成绩：");
            double grade = sc.nextInt();
            System.out.print("请输入学生的学科：");
            String subject = sc.next();
            System.out.print("请输入学生的学科编号：");
            String number = sc.next();
            
            Student s = new Student(ID, name, grade, new Subject(subject, number));
            System.out.println("添加成功！！！！！");
            return s;
    }
    
    //获得指定学生成绩
    public  void println(List<Student> list) {
        System.out.print("请输入您要查询的学生姓名为：");
        String name = sc.next();
        for (int i = 0; i < list.size(); i++) {
            if ((list.get(i).getName().equals(name))) {
                System.out.println("您查找的学生" + name + "的成绩为：" + list.get(i).getGrade() );
            }else {
                if (i == list.size() - 1) {//如果最后一次还没有找学生则输出学生不存在
                    System.out.println("对不起，您要查找的学生不存在");
                }
            }
            
        }
        
    }
    
    //获得指定学号的成绩
    public  void  numberGrade(List<Student> list) {
        System.out.print("请输入您要查询的学生学号为：");
        String ID = sc.next();
        for (int i = 0; i < list.size(); i++) {
            if ((list.get(i).getID().equals(ID))) {
                System.out.println("您查找学号为" + ID + "的成绩为：" + list.get(i).getGrade() );
                break;
            }else {
                if (i == list.size() - 1) {//如果最后一次还没有找学生则输出学生不存在
                    System.out.println("对不起，您要查找的学生不存在");
                }
            }
        }
        
    }
    
    //根据学生ID修改姓名
    public  void updataName(List<Student> list) {
        System.out.print("请输入您要修改姓名的学生ID为：");
        String ID = sc.next();
        for (int i = 0; i < list.size(); i++) {
            if ((list.get(i).getID().equals(ID))) {
                System.out.println("请输入要修改的姓名");
                String name = sc.next();
                list.get(i).setName(name);
                list.set(i, new Student( list.get(i).getID(), list.get(i).getName(), list.get(i).getGrade(), list.get(i).getSubject()));
                System.out.println("ID为" + ID + "现在姓名修改为：" + list.get(i).getName() );
                break;
            }else {
                if (i == list.size() - 1) {//如果最后一次还没有找学生则输出学生不存在
                    System.out.println("对不起，您要查找的学生不存在");
                }
            }
        }
        
    }
    
    //根据姓名修改指定学科成绩
    public  void updataGrade(List<Student> list) {
        System.out.print("请输入您要修改成绩的学生的姓名：");
        String name = sc.next();
        for (int i = 0; i < list.size(); i++) {
            if ((list.get(i).getID().equals(name))) {
                System.out.println("请输入要修改的姓名");
                double grade = sc.nextInt();
                list.get(i).setGrade(grade);
                list.set(i, new Student( list.get(i).getID(), list.get(i).getName(), list.get(i).getGrade(), list.get(i).getSubject()));
                System.out.println("姓名为" + name + "现在成绩修改为：" + list.get(i).getGrade() );
                break;
            }else {
                if (i == list.size() - 1) {//如果最后一次还没有找学生则输出学生不存在
                    System.out.println("对不起，您要查找的学生不存在");
                }
            }
        }
        
    }
    
    //删除指定学生及成绩
    public  void delect(List<Student> list) {
        System.out.print("请输入您要删除学生的姓名：");
        String name = sc.next();
        for (int i = 0; i < list.size(); i++) {
            if ((list.get(i).getName().equals(name))) {
                list.remove(list.get(i));
                System.out.println("这个学生现在被你删除的连渣都不剩了，开心吧！！");
                }
            }
    }
    
    
    
    

}

 

4.主方法

 

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;


public class Text {
    static Scanner sc = new Scanner(System.in);
    public static void main(String[] args) {
        List<Student> list = new ArrayList();
        Main main = new Main();
        int select = 1;
        int count = 0;
        while (select != 0) {
            main.infa();
            select = sc.nextInt();//功能选择
            
            switch (select) {
            case 1: list.add(main.create());
                    count++;
                    System.out.println("已添加学生人数为:" + count );
            
            break;
            
            case 2:  main.println(list);
            break;
            
            case 3:  main.numberGrade(list);
            break;
            
            case 4:  main.updataName(list);
            break;
            
            case 5:  main.updataGrade(list);
            break;
            
            case 6:  main.delect(list);
            break;
            default:
                break;
            }
        }
        
        
        
    }

}

 

 

运行截图

在JDBC分类中有连接数据库的的demo