Java学习-用JDBC通过CURD实现简单的业务，用户登陆，学生管理

上一篇已经学完了JDBC，这篇讲一下基本的CURD实现简单的业务。

基本准备

数据表两张分别是user表和学生表student1结构如下

分别对应，用户id，用户名，密码，错误次数，状态（是否锁定）

学生表，分别对应，学号，姓名，性别，年龄，地址
mysql的jar包
数据插入


SET FOREIGN_KEY_CHECKS=0;-- ----------------------------
-- Table structure for student1
-- ----------------------------
DROP TABLE IF EXISTS `student1`;
CREATE TABLE `student1` (`sid` int(11) NOT NULL AUTO_INCREMENT,`sname` varchar(8) NOT NULL,`sgender` char(255) NOT NULL,`sage` int(3) DEFAULT NULL,`saddress` varchar(255) DEFAULT NULL,PRIMARY KEY (`sid`)
) ENGINE=InnoDB AUTO_INCREMENT=37 DEFAULT CHARSET=utf8;-- ----------------------------
-- Records of student1
-- ----------------------------
INSERT INTO `student1` VALUES ('1', '李青', '男', '48', '德玛西亚');
INSERT INTO `student1` VALUES ('2', '艾瑞莉娅', '女', '26', '艾欧尼亚');
INSERT INTO `student1` VALUES ('3', '锐雯', '女', '36', '艾欧尼亚');
INSERT INTO `student1` VALUES ('4', '凯特琳', '女', '28', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('5', '蔚', '女', '28', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('6', '金克丝', '女', '28', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('7', '普朗克', '男', '45', '比尔吉沃特');
INSERT INTO `student1` VALUES ('8', '好运姐', '女', '36', '比尔吉沃特');
INSERT INTO `student1` VALUES ('9', '锤石', '男', '96', '暗影岛');
INSERT INTO `student1` VALUES ('10', '佛耶戈', '男', '52', '暗影岛');
INSERT INTO `student1` VALUES ('11', '雷欧娜', '女', '36', '巨神峰');
INSERT INTO `student1` VALUES ('12', '阿兹尔', '男', '108', '恕瑞玛');
INSERT INTO `student1` VALUES ('13', '内瑟斯', '男', '118', '恕瑞玛');
INSERT INTO `student1` VALUES ('14', '雷克顿', '男', '118', '恕瑞玛');
INSERT INTO `student1` VALUES ('15', '艾希', '女', '38', '弗雷尔卓德');
INSERT INTO `student1` VALUES ('16', '瑟庄妮', '女', '45', '弗雷尔卓德');
INSERT INTO `student1` VALUES ('17', '丽桑卓', '女', '82', '弗雷尔卓德');
INSERT INTO `student1` VALUES ('18', '亚索', '男', '35', '艾欧尼亚');
INSERT INTO `student1` VALUES ('19', '永恩', '男', '36', '艾欧尼亚');
INSERT INTO `student1` VALUES ('20', '德莱厄斯', '男', '36', '诺克萨斯');
INSERT INTO `student1` VALUES ('21', '卡特琳娜', '女', '32', '诺克萨斯');
INSERT INTO `student1` VALUES ('22', '德莱文', '男', '30', '诺克萨斯');
INSERT INTO `student1` VALUES ('23', '斯维因', '男', '50', '诺克萨斯');
INSERT INTO `student1` VALUES ('24', '杰斯', '男', '40', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('25', '维克托', '男', '41', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('26', '沃里克', '男', '45', '祖安');
INSERT INTO `student1` VALUES ('27', '蒙多', '男', '40', '祖安');
INSERT INTO `student1` VALUES ('28', '凯尔', '女', '139', '烈焰阳刚');
INSERT INTO `student1` VALUES ('29', '莫甘娜', '女', '139', '烈焰阳刚');
INSERT INTO `student1` VALUES ('30', '卡蜜尔', '女', '30', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('31', '菲奥娜', '女', '35', '皮尔特沃夫');
INSERT INTO `student1` VALUES ('32', '拉克丝', '女', '30', '德玛西亚');
INSERT INTO `student1` VALUES ('34', '乐芙兰', '女', '32', '黑色玫瑰');
INSERT INTO `student1` VALUES ('35', '亚托克斯', '男', '108', '恕瑞玛');
INSERT INTO `student1` VALUES ('36', '沃利贝尔', '男', '89', '无畏先锋');


SET FOREIGN_KEY_CHECKS=0;-- ----------------------------
-- Table structure for user
-- ----------------------------
DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (`uid` int(11) NOT NULL AUTO_INCREMENT,`username` varchar(16) NOT NULL,`password` varchar(16) NOT NULL,`wrong_times` int(1) NOT NULL,`status` int(1) NOT NULL DEFAULT '0',PRIMARY KEY (`uid`)
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES ('1', '奥特曼', '111111', '0', '0');

需求分析

要求实现模拟用户登陆

如果用户名不存在，则提示用户名不存在。密码错误则提示密码错误。
用户名输入正确密码输入正确，可以正常登陆系统。否则不允许登陆。
并且密码输错三次，对帐号进行锁定。再次登陆时提示已锁定。
只要未满三次错误，输入正确，则错误次数重置。
模拟学生管理，应包含以下功能

对数据表中的所有学生进行输出
可以根据关键字段模糊查询学生
根据学号，对学生信息进行修改
根据学号，对学生进行单条删除
系统功能

可以实现用户通过输入指令对所有功能进行操作

代码编写

目录层级如下：

entity包

Student

package com.lzl.StudentManage.entity;import java.util.Date;public class Student {private Integer sid;private String sname;private String sgender;private Integer sage;private String saddress;public Student(Integer sid, String sname, String sgender, Integer sage, String saddress) {this.sid = sid;this.sname = sname;this.sgender = sgender;this.sage = sage;this.saddress = saddress;}public Student() {}public Integer getSid() {return sid;}public void setSid(Integer sid) {this.sid = sid;}public String getSname() {return sname;}public void setSname(String sname) {this.sname = sname;}public String getSgender() {return sgender;}public void setSgender(String sgender) {this.sgender = sgender;}public Integer getSage() {return sage;}public void setSage(Integer sage) {this.sage = sage;}public String getSaddress() {return saddress;}public void setSaddress(String saddress) {this.saddress = saddress;}@Overridepublic String toString() {return "Student{" +"sid=" + sid +", sname='" + sname + '\'' +", sgender='" + sgender + '\'' +", sage=" + sage +", saddress='" + saddress + '\'' +'}';}
}

User

package com.lzl.StudentManage.entity;public class User {private Integer uid;private String username;private String password;private Integer wrong_times;private Integer status;public User(Integer uid, String username, String password, Integer wrong_times, Integer status) {this.uid = uid;this.username = username;this.password = password;this.wrong_times = wrong_times;this.status = status;}public User() {}public Integer getUid() {return uid;}public void setUid(Integer uid) {this.uid = uid;}public String getUsername() {return username;}public void setUsername(String username) {this.username = username;}public String getPassword() {return password;}public void setPassword(String password) {this.password = password;}public Integer getWrong_times() {return wrong_times;}public void setWrong_times(Integer wrong_times) {this.wrong_times = wrong_times;}public Integer getStatus() {return status;}public void setStatus(Integer status) {this.status = status;}@Overridepublic String toString() {return "User{" +"uid=" + uid +", username='" + username + '\'' +", password='" + password + '\'' +", wrong_times=" + wrong_times +", status=" + status +'}';}
}

util包

DBUtil

package com.lzl.StudentManage.util;import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;public class DBUtil {private static final String driver = "com.mysql.jdbc.Driver";private static final String url = "jdbc:mysql://localhost:3306/qianfeng";private static final String user = "root";private static final String password = "123456";public static Connection getConnection() {Connection con = null;try {Class.forName(driver);con = DriverManager.getConnection(url, user, password);} catch (ClassNotFoundException e) {e.printStackTrace();} catch (SQLException e) {e.printStackTrace();}return con;}public static void closeAll(Connection conn, Statement state,ResultSet rs) {try {if (conn != null){conn.close();}if (state != null){state.close();}if(rs != null){rs.close();}} catch (SQLException e) {e.printStackTrace();}}public static int executeUpdate(String sql,ArrayList params){//创建连接Connection conn = null;//创建平台PreparedStatement ps = null;try {conn = getConnection();//预编译sql语句ps = conn.prepareStatement(sql);//设置参数for (int i = 0; i < params.size(); i++) {ps.setObject(i + 1, params.get(i));}//返回受影响行数return ps.executeUpdate();} catch (SQLException e) {e.printStackTrace();} finally {closeAll(conn, ps,null);}return -1;}}

StringUtil

package com.lzl.StudentManage.util;/*** 处理字符串工具类*/
public class StringUtil {/***  是null 或者 是 空字符串*/public static boolean isNull(Object obj) {//将Object转为StringString str = (String)obj;//返回true | falsereturn (str == null) || (str.length() == 0);}}

controller包

LoginController

package com.lzl.StudentManage.controller;import com.lzl.StudentManage.entity.User;
import com.lzl.StudentManage.util.DBUtil;import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;public class LoginController {//获得连接private  Connection conn = null;//预编译处理对象private  PreparedStatement pst = null;//结果集private ResultSet rts = null;//注入student控制层static StudentController studentController = new StudentController();/*** 登录方法*/public void getLogin(){Scanner scanner = new Scanner(System.in);String key = "y";try {conn = DBUtil.getConnection();//预编译String sql = "select * from user where username = ? ";pst = conn.prepareStatement(sql);do{System.out.println("请输入帐号：");String name = scanner.nextLine();pst.setString(1,name);System.out.println("请输入密码");String pwd = scanner.nextLine();System.out.println("正在登陆");for (int i = 0; i < 3; i++) {Thread.sleep(500);System.out.print(".");}System.out.println();rts = pst.executeQuery();List<User> list = new ArrayList<>();while (rts.next()){User user = new User();user.setUid(rts.getInt("uid"));user.setUsername(rts.getString("username"));user.setPassword(rts.getString("password"));user.setWrong_times(rts.getInt("wrong_times"));user.setStatus(rts.getInt("status"));list.add(user);}if (list.size()!=0){for (User user : list) {if(user.getStatus()!=1){if(user.getPassword().equals(pwd)){System.out.println("登陆成功，欢迎回来！");String sql1 = "update user set wrong_times = 0 where username = ?";PreparedStatement pst1 = conn.prepareStatement(sql1);pst1.setString(1,name);pst1.executeUpdate();studentController.getMenu();key = "n";DBUtil.closeAll(null,pst1,rts);}else {if (user.getWrong_times()<3){String sql2 = "update user set wrong_times = wrong_times + 1 where username = ?";PreparedStatement pst2 = conn.prepareStatement(sql2);pst2.setString(1,name);pst2.executeUpdate();System.out.println("密码输入错误，您已输错"+(user.getWrong_times()+1)+"次！");System.out.println("错误3次，帐号将被锁定！");System.out.println("是否重试？y/n");key = scanner.nextLine();DBUtil.closeAll(null,pst2,rts);}if(user.getWrong_times()==3){String sql3 = "update user set status = 1 where username = ?";PreparedStatement pst3 = conn.prepareStatement(sql3);pst3.setString(1,name);pst3.executeUpdate();System.out.println("密码错误已达3次,您的帐号疑似处于不安全状态！帐号已被锁定！！");System.out.println("请联系管理员解锁！");key = "n";DBUtil.closeAll(null,pst3,rts);}}}else {System.out.println("密码错误已达3次,您的帐号疑似处于不安全状态！帐号已被锁定！！");System.out.println("请联系管理员解锁！");key = "n";}}}else {System.out.println("用户名不存在！");System.out.println("是否重试！y/n");key = scanner.nextLine();}}while (key.equals("y"));} catch (Exception e) {e.printStackTrace();} finally {DBUtil.closeAll(conn,pst,rts);}}
}

StudentController

package com.lzl.StudentManage.controller;import com.lzl.StudentManage.entity.Student;
import com.lzl.StudentManage.service.serviceimpl.StudentServiceImpl;import java.util.*;public class StudentController {static StudentServiceImpl impl = new StudentServiceImpl();static Scanner scanner = new Scanner(System.in);/*** 查询（条件）所有用户* @param student 查询的关键字* @return 所有符合条件的用户*/private static List<Student> getAll(Student student){Map<String, Object> map = new HashMap<>();map.put("sid",student.getSid());map.put("sname",student.getSname());map.put("sgender",student.getSgender());map.put("sage",student.getSage());map.put("saddress",student.getSaddress());return impl.getAll(map);}/***多条件查询用户*/public  void searchPrintAll(){System.out.println("您可以进行关键字查询，请选择您要查询的关键字类别");System.out.println("1:学号，2:姓名，3:性别，4:年龄，5:家庭住址");Integer key = scanner.nextInt();Student student =  searchWords(key);List<Student> list = getAll(student);if (list.size()>0){System.out.println("查询信息如下");System.out.println("学号\t姓名\t\t性别 年龄 家庭住址");for (Student s : list) {if (s.getSname().length()>=2){if (s.getSage() > 99){System.out.println(s.getSid()+"\t|"+s.getSname()+"\t|"+s.getSgender()+"\t|"+s.getSage()+"\t|"+s.getSaddress());}else {System.out.println(s.getSid()+"\t|"+s.getSname()+"\t|"+s.getSgender()+"\t|"+s.getSage()+"\t\t|"+s.getSaddress());}} else if(s.getSname().length()==1){System.out.println(s.getSid()+"\t|"+s.getSname()+"\t\t|"+s.getSgender()+"\t|"+s.getSage()+"\t\t|"+s.getSaddress());}else {System.out.println(s.getSid()+"\t|"+s.getSname()+"\t\t|"+s.getSgender()+"\t|"+s.getSage()+"\t|"+s.getSaddress());}}}else {System.out.println("没有相关数据！");}}/*** 无条件输出所有学生信息*/private void printAll() {Student student = new Student();List<Student> list =  getAll(student);System.out.println("学号\t姓名\t\t性别 年龄 \t家庭住址");for (Student s : list) {if (s.getSname().length()>=2){if (s.getSage() > 99){System.out.println(s.getSid()+"\t|"+s.getSname()+"\t|"+s.getSgender()+"\t|"+s.getSage()+"\t|"+s.getSaddress());}else {System.out.println(s.getSid()+"\t|"+s.getSname()+"\t|"+s.getSgender()+"\t|"+s.getSage()+"\t\t|"+s.getSaddress());}} else if(s.getSname().length()==1){System.out.println(s.getSid()+"\t|"+s.getSname()+"\t\t|"+s.getSgender()+"\t|"+s.getSage()+"\t\t|"+s.getSaddress());}else {System.out.println(s.getSid()+"\t|"+s.getSname()+"\t\t|"+s.getSgender()+"\t|"+s.getSage()+"\t|"+s.getSaddress());}}}/*** 设置多条件查询的关键字* @param key 查询编号* @return 一个用于多条件查询的学生实体*/private static Student searchWords(Integer key) {Student student = new Student();if(key==1){System.out.println("请输入您想要查询的学号：");Integer sid = scanner.nextInt();student.setSid(sid);}else if (key==2){System.out.println("请输入您想要查询的姓名关键字：");String sname = scanner.next();student.setSname(sname);}else if (key == 3){System.out.println("请输入您想要查询的性别（男/女）：");String sgender = scanner.next();student.setSgender(sgender);}else if (key == 4){System.out.println("请输入您想要查询的年龄：");Integer sage = scanner.nextInt();student.setSage(sage);}else if (key == 5){System.out.println("请输入您想要查询的家庭住址：");String saddress = scanner.next();student.setSaddress(saddress);}else {System.out.println("你是来捣乱的吧！乱输入，给你所有的数据，玩去吧！");}return student;}/*** 获得功能菜单*/public void getMenu() {int key = 0;do{System.out.println("==============================功能菜单==========================");System.out.println("您有以下功能：1:输出所有学生信息，2:模糊查询学生，3:新增学生，4:修改学生信息，" +"5:删除学生信息，0:退出系统");key = scanner.nextInt();switch (key){case 1:printAll();break;case 2:searchPrintAll();break;case 3:addNew();break;case 4:updateBySid();break;case 5:deleteBySid();break;case 0:break;default:System.out.println("你是来找茬的吧？");break;}}while (key!=0);System.out.println("您已成功退出！");}/*** 新增方法*/private void addNew() {System.out.println("正在进行新增操作");System.out.println("请输入新增学生姓名：");String sname = scanner.next();System.out.println("输入新增学生性别：");String sgender = scanner.next();System.out.println("输入新增学生年龄");Integer sage = scanner.nextInt();System.out.println("输入学生地址：");String saddress = scanner.next();Student student = new Student(null,sname,sgender,sage,saddress);System.out.println("新增学生信息如下：");System.out.println("姓名:"+sname+"|性别:"+sgender+"|年龄:"+sage+"|地址:"+saddress);Integer key = impl.insertStudent(student);if (key > 0){System.out.println("新增成功！");}else {System.out.println("新增失败！");}}/*** 修改方法*/private void updateBySid() {System.out.println("正在进行修改操作");System.out.println("请输入要修改学生的学号：");String sid = scanner.next();System.out.println("请输入新的姓名：");String sname = scanner.next();System.out.println("输入新的学生性别：");String sgender = scanner.next();System.out.println("输入新的学生年龄：");String sage = scanner.next();System.out.println("输入新的学生地址：");String saddress = scanner.next();System.out.println("修改后学生信息如下：");System.out.println("姓名:"+sname+"|性别:"+sgender+"|年龄:"+sage+"|地址:"+saddress);ArrayList<String> parms = new ArrayList<>();parms.add(sname);parms.add(sgender);parms.add(sage);parms.add(saddress);parms.add(sid);//此处id要最后放入集合，因为DBUtil中字符串拼接按添加的先后顺序//update语句的where子句在最后，所以sid放再最后，其它字段按原顺序Integer key = impl.updateStudent(parms);if (key > 0){System.out.println("修改成功！");}else {System.out.println("修改失败！");}}/*** 删除方法*/private void deleteBySid() {System.out.println("正在进行删除操作");System.out.println("请输入要删除的学生学号：");String sid = scanner.next();Integer key = impl.deleteStudent(sid);if (key > 0){System.out.println("删除成功！");}else {System.out.println("删除失败！");}}}

service包

StudentService

package com.lzl.StudentManage.service;import com.lzl.StudentManage.entity.Student;
import com.lzl.day029.User;import java.util.ArrayList;
import java.util.List;
import java.util.Map;public interface StudentService {/*** 获得所有用户* @param keys 多条件查询，分页参数* @return 所有符合条件用户集合*/List<Student> getAll(Map<String,Object> keys);/*** 新增学生* @param student 新增的学生信息* @return 受影响行数*/Integer insertStudent(Student student);/*** 修改数据* @param params 字符串集合* @return 受影响行数*/Integer updateStudent(ArrayList<String> params);/**** @param sid 学生学号* @return 受影响行数*/Integer deleteStudent(String sid);}

StudentServiceImpl

package com.lzl.StudentManage.service.serviceimpl;import com.lzl.StudentManage.entity.Student;
import com.lzl.StudentManage.service.StudentService;
import com.lzl.StudentManage.util.DBUtil;
import com.lzl.StudentManage.util.StringUtil;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;public class StudentServiceImpl implements StudentService {//获得连接private  Connection conn = null;//预编译处理对象private  PreparedStatement pst = null;//结果集private ResultSet rts = null;//参数集合private ArrayList<Object> params = null;/*** 获得所有用户** @param keys 多条件查询，分页参数* @return 所有用户集合*/@Overridepublic List<Student> getAll(Map<String, Object> keys) {//构建数据存放容器List<Student> list = new ArrayList<>();//构建查询所需参数的容器params = new ArrayList<>();//初始化sql语句  设置1=1，确保语句能执行不报错String sql = "select * from student1 where 1 = 1";//拼串，将多条件查询需要的参数全部拼接过来//判断不为空，则进行拼接if(!StringUtil.isNull(keys.get("sid"))){//将sql语句进行拼接，注意and开头有一个空格sql+=" and sid = ?";//将后边要填补占位符的参数从Map（Controller传过来的参数）集合添加进参数容器params.add(keys.get("sid"));}if(!StringUtil.isNull(keys.get("sname"))){//将sql语句进行拼接，注意and开头有一个空格sql+=" and sname like ?";//将后边要填补占位符的参数从Map（Controller传过来的参数）集合添加进参数容器params.add("%"+keys.get("sname")+"%");}if(!StringUtil.isNull(keys.get("sgender"))){sql+=" and sgender = ?";params.add(keys.get("sgender"));}if(!StringUtil.isNull(keys.get("sage"))){sql+=" and sage = ?";params.add(keys.get("sage"));}if(!StringUtil.isNull(keys.get("saddress"))){sql+=" and saddress like ?";params.add("%"+keys.get("saddress")+"%");}sql+=" order by sid";try {//获取连接conn = DBUtil.getConnection();//预编译处理sqlpst = conn.prepareStatement(sql);//设置参数for (int i = 0; i < params.size(); i++) {pst.setObject(i+1,params.get(i));}//执行sql获得数据rts = pst.executeQuery();//处理数据while (rts.next()){//建一个对象Student student = new Student();//将所有结果集中的值取出，赋给对象student.setSid(rts.getInt("sid"));student.setSname(rts.getString("sname"));student.setSgender(rts.getString("sgender"));student.setSage(rts.getInt("sage"));student.setSaddress(rts.getString("saddress"));//将对象放到容器内list.add(student);}} catch (SQLException e) {e.printStackTrace();}finally {//关流DBUtil.closeAll(conn,pst,rts);}return list;}/*** 新增学生** @param student 新增的学生信息* @return 受影响行数*/@Overridepublic Integer insertStudent(Student student) {//给一个默认返回值Integer key = 0;try {//获得连接conn = DBUtil.getConnection();//写sql语句String sql = "insert into student1(sname,sgender,sage,saddress) values (?,?,?,?)";//预编译sqlpst = conn.prepareStatement(sql);//将插入的值赋给占位符pst.setString(1,student.getSname());pst.setString(2,student.getSgender());pst.setInt(3,student.getSage());pst.setString(4,student.getSaddress());//交给executeUpdate执行，key接收受影响行数key = pst.executeUpdate();} catch (SQLException e) {e.printStackTrace();}finally {//关流DBUtil.closeAll(conn,pst,rts);}return key;}/***修改* @param params 字符串集合* @return 受影响行数*/@Overridepublic Integer updateStudent(ArrayList<String> params) {//给一个默认返回值Integer key = 0;//编写sql语句String sql = "update student1 set sname = ?,sgender = ?," +"sage = ?,saddress = ? where sid = ?";//将controller传过来的字符串集合，和sql语句交给DBUtil的方法执行，用key接收受影响行数key = DBUtil.executeUpdate(sql,params);return key;}/**删除* @param sid 学生学号* @return 受影响行数*/@Overridepublic Integer deleteStudent(String sid) {Integer key = 0;if (!StringUtil.isNull(sid)){String sql =  String.format("delete from student1 where sid in(%s)",sid);key = DBUtil.executeUpdate(sql,params);}return key;}
}

test包

测试类

package com.lzl.StudentManage.test;import com.lzl.StudentManage.controller.LoginController;
import com.lzl.StudentManage.controller.StudentController;
import java.util.Scanner;public class WebModel {static StudentController studentController = new StudentController();static LoginController loginController = new LoginController();static Scanner scanner = new Scanner(System.in);public static void main(String[] args) {System.out.println("============欢迎来到学生管理系统============");System.out.println("请您登陆");loginController.getLogin();}}

附上效果演示

演示CRUD

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Java学习-用JDBC通过CURD实现简单的业务，用户登陆，学生管理

基本准备

需求分析

代码编写

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