java 银行管理系统（连接数据库Mysql）
java 银行管理系统（连接数据库Mysql）
- 逻辑与功能图
-
- 实现逻辑
- 功能图
- 代码
逻辑与功能图
实现逻辑
程序共有三个文件
Bankmangement.java:包括程序运行的主函数，方法等
User.java：实体类，用于创建对象
JDBCUtils：对数据库方法进行封装
功能图
1.User实体类
数据库共有三张表，分别是admin管理员帐号，user用户账号，record用户记录。
2.Bankmangement功能图
代码
Bankmangement
package bank;
import java.sql.*;
import java.text.SimpleDateFormat;
import java.util.*;
public class Bankmanagement { //知识点2：类的声明
private static Scanner sc = new Scanner(System.in); //知识点3:类成员的访问控制（私有，只能被这个类本身访问）
public static void main(String[] args) {
menu();
}
public static void menu(){
System.out.println("-------------------欢迎进入银行储蓄系统----------------");
System.out.println("-------------------请选择您的登录方式------------------");
System.out.println("-------------------0、登陆管理员账户-----------------");
System.out.println("-------------------1、登录用户账户-----------------");
System.out.println("-------------------2、注册账户-----------------");
String select = sc.next();
switch (select) {
case "0":
//登录
login(); //知识点8：调用方法
break;
case "1":
//登录
login1(); //知识点8：调用方法
break;
case "2":
//注册：将注册操作定义到一个方法中然后调用方法
register();
break;
}
}
//注册账户
public static void register() {
System.out.println("--------------欢迎进入注册页面-----------");
Random r = new Random();
System.out.println("请输入账户名：");
String username = sc.next();
System.out.println("请输入账户密码");
String password = sc.next();
System.out.println("请输入手机号：");
String phonenumber = sc.next();
System.out.println("请输入地址：");
String address = sc.next();
System.out.println("请输入账户余额：");
float balance = sc.nextFloat();
boolean flag = new Bankmanagement().adminlogin(username,password);
while (!flag){
int id = r.nextInt(100000,999999);
Connection conn = null;
Statement stmt = null;
PreparedStatement pstmt = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "insert into user(username,id,password,phonenumber,address,balance) values(?,?,?,?,?,?)";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,username);
pstmt.setInt(2,id);
pstmt.setString(3,password);
pstmt.setString(4,phonenumber);
pstmt.setString(5,address);
pstmt.setDouble(6,balance);
//判断
int count = pstmt.executeUpdate();
if (count>0){
System.out.println("注册成功");
System.out.println("您的id账号为:"+id);
menu();
}else{
System.out.println("注册失败");
return;
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
}
System.out.println("账户已存在请重新输入！");
}
public boolean judgement(String username){
if (username == null){
return false;
}
//数据库连接
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from user where username = ?";
//获取执行对象
pstmt = conn.prepareStatement(sql);
//给问号赋值
pstmt.setString(1,username);
//执行查询
rs = pstmt.executeQuery();
//判断
return rs.next();
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,pstmt,conn);
}
return false;
}
//登录管理员账户
public static void login(){
System.out.println("--------欢迎进入登录页面--------");
for (int i = 1; i <= 3; i++) {
System.out.println("请输入管理员账号");
String username = sc.next();
System.out.println("请输入管理员密码");
String password = sc.next();
boolean flag = new Bankmanagement().adminlogin(username,password);
while (flag) { //知识点12：while语句
System.out.println("请录入您要进行的操作");
System.out.println("1、添加账户");
System.out.println("2、所有账户个人信息的查询");
System.out.println("3、删除账户");
System.out.println("4、退出系统");
String num = sc.next();
switch (num) { //知识点13：switch选择语句
case "1":
Add();
break;
case "2":
checkAllUsers();
break;
case "3":
//注册：将注册操作定义到一个方法中然后调用方法
Delete();
break;
case "4":
menu();
break;
}
}
System.out.println("登录失败,用户名或密码错误");
}
System.out.println("您的3次机会已经用完，自动退出系统");
System.exit(0);
}
public boolean adminlogin(String username,String password){
if (username == null||password == null){
System.out.println("!!!!");
return false;
}
//数据库连接
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from admin where username = ? and password = ?";
//获取执行对象
pstmt = conn.prepareStatement(sql);
//给问号赋值
pstmt.setString(1,username);
pstmt.setString(2,password);
//执行查询
rs = pstmt.executeQuery();
//判断
return rs.next();
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,pstmt,conn);
}
return false;
}
//登录账户
public static void login1(){
System.out.println("--------欢迎进入登录页面--------");
for (int i = 1; i <= 3; i++) {
System.out.println("请录入您要登录的用户名");
String username = sc.next();
System.out.println("请录入您的id");
int id = sc.nextInt();
System.out.println("请录入您要登录的密码");
String password = sc.next();
boolean flag = new Bankmanagement().userlogin(username,password,id);
while (flag) { //知识点12：while语句
User u = new User(username,id,password);
System.out.println("请录入您要进行的操作");
System.out.println("1、修改账户");
System.out.println("2、用户密码的修改");
System.out.println("3、当前账户个人信息的查询");
System.out.println("4、存钱");
System.out.println("5、取钱");
System.out.println("6、转账");
System.out.println("7、打印清单");
System.out.println("8、注销账户");
System.out.println("9、退出系统");
String num2 = sc.next();
switch (num2) { //知识点13：switch选择语句
case "1":
updateMsg(u);
break;
case "2":
updatePwd(u);
break;
case "3":
updateOne (u);
break;
case "4":
saveMoney(u);
break;
case "5":
drawMoney(u);
break;
case "6":
transferMoney(u);
break;
case "7":
print(u);
break;
case "8":
cancel(u);
break;
case "9":
menu();
break;
}
}
System.out.println("登录失败");
}
System.out.println("您的3次机会已经用完，自动退出系统");
System.exit(0);
}
public boolean userlogin(String username,String password,int id){
if (username == null||password == null||id ==0){
System.out.println("!!!!");
return false;
}
//数据库连接
Connection conn = null;
Statement stmt = null;
ResultSet rs = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from user where username = '"+username+"'and id = '"+id+"' and password = '"+password+"'";
//获取执行对象
stmt = conn.createStatement();
//执行查询
rs = stmt.executeQuery(sql);
//判断
return rs.next();
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,stmt,conn);
}
return false;
}
//修改用户信息
public static void updateMsg(bank.User u) { //知识点：声明一个方法
System.out.println("----------欢迎进入修改账户信息模块----------");
Connection conn = null;
PreparedStatement pstmt = null;
try{
System.out.println("请录入您要修改的手机号：");
String phonenumber = sc.next();
System.out.println("请录入您要修改的地址：");
String address = sc.next();
System.out.println("请录入您要修改的余额：");
float balance = Float.parseFloat(sc.next());
conn = JDBCUtils.getConnection();
//定义sql语句
String sql="update user set phonenumber=?,address=?,balance=? where username=?";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,phonenumber);
pstmt.setString(2,address);
pstmt.setDouble(3,balance);
pstmt.setString(4,u.getName());
// pstmt.executeUpdate();
//获取执行对象
// stmt = conn.createStatement();
//执行查询
// rs = stmt.executeQuery(sql);
//判断
int count = pstmt.executeUpdate();
if (count>0){
System.out.println("修改成功");
}else{
System.out.println("修改失败");
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
}
//删除账户
public static void Delete()
{
System.out.println("----------欢迎进入用户信息删除模块----------");
System.out.println("请录入您要删除的用户名");
String username = sc.next();
boolean flag = new Bankmanagement().judge(username);
while (flag){
Connection conn = null;
Statement stmt = null;
PreparedStatement pstmt = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "delete from user where username=?";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,username);
// pstmt.executeUpdate();
//获取执行对象
// stmt = conn.createStatement();
//执行查询
// rs = stmt.executeQuery(sql);
//判断
int count =pstmt.executeUpdate();
if (count>0){
System.out.println("删除成功");
return;
}else{
System.out.println("删除失败,请重试！");
Delete();
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
}
System.out.println("你输入的账号不存在，请重新输入！");
Delete();
}
//添加用户
public static void Add(){
System.out.println("请输入增加的账户名：");
String username = sc.next();
System.out.println("请输入账户密码");
String password = sc.next();
System.out.println("请输入手机号：");
String phonenumber = sc.next();
System.out.println("请输入地址：");
String address = sc.next();
System.out.println("请输入账户余额：");
float balance = sc.nextFloat();
Random r = new Random();
// bank.User user2 = new bank.User(username , number, password, address, balance); //知识点：构造方法
// userlist.add(user2); //知识点19：调用集合添加方法
//
// System.out.println("该用户添加成功！！");
// return;
int id = r.nextInt(100000,999999);
Connection conn = null;
Statement stmt = null;
PreparedStatement pstmt = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "insert into user(username,id,password,phonenumber,address,balance) values(?,?,?,?,?,?)";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,username);
pstmt.setInt(2,id);
pstmt.setString(3,password);
pstmt.setString(4,phonenumber);
pstmt.setString(5,address);
pstmt.setDouble(6,balance);
// pstmt.executeUpdate();
//获取执行对象
// stmt = conn.createStatement();
//执行查询
// rs = stmt.executeQuery(sql);
//判断
int count = pstmt.executeUpdate();
if (count>0){
System.out.println("添加成功");
System.out.println("id账号为:"+id);
}else{
System.out.println("添加失败");
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
}
//修改密码
public static void updatePwd(bank.User u) {
System.out.println("请录入您的原密码：");
String oldPwd = sc.next();
boolean flag = new Bankmanagement().userlogin(u.getName(),oldPwd, u.getId());
while (flag) { //知识点20：equals方法
System.out.println("您的原密码输入正确，请录入您要修改的新密码：");
String newPwd = sc.next();
Connection conn = null;
PreparedStatement pstmt = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql="update user set password=? where username=?";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,newPwd);
pstmt.setString(2,u.getName());
// pstmt.executeUpdate();
//获取执行对象
// stmt = conn.createStatement();
//执行查询
// rs = stmt.executeQuery(sql);
//判断
int count = pstmt.executeUpdate();
if (count>0){
System.out.println("修改成功");
login1();
}else{
System.out.println("修改失败");
return;
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
}
System.out.println("您的原密码输入错误，密码修改失败");
}
//当前账户个人信息查询
public static void updateOne (bank.User u){
// System.out.println("查询信息如下：");
// System.out.println("用户名 手机号 密码 住址 余额");
// System.out.println(u.getName() + " " + u.getNumber() + " " + u.getPassword() + " " + u.getAddress()+ " " + u.getBalance());
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
// User user = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from user where id = '"+u.getId()+"'";
// pstmt.setInt(1,u.getId());
//获取执行对象
pstmt = conn.prepareStatement(sql);
//执行查询
rs = pstmt.executeQuery();
while(rs.next()) {
//获取数据
String name = rs.getString("username");
int id = rs.getInt("id");
String number = rs.getString("phonenumber");
String password = rs.getString("password");
String address = rs.getString("address");
double balance = rs.getDouble("balance");
System.out.println("用户名 id 手机号 密码 住址 余额");
System.out.println(name + " " + id + " " + number + " " + password + " " + address + " " + balance);
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,pstmt,conn);
}
}
//所有用户个人信息查询
public static void checkAllUsers() {
ArrayList<User> list = new Bankmanagement().findall();
System.out.println("用户名 手机号 密码 住址 余额");
for (bank.User u : list) { //知识点21：遍历
System.out.println(u.getName() + " " + u.getNumber() + " " + u.getPassword() + " " + u.getAddress()+ " " +u.getBalance());
}
}
public ArrayList<User> findall(){
//数据库连接
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
ArrayList<User> list = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from user";
//获取执行对象
pstmt = conn.prepareStatement(sql);
//执行查询
rs = pstmt.executeQuery();
User user = null;
list = new ArrayList<User>();
//便利
while(rs.next()){
//获取数据
String name = rs.getString("username");
int id = rs.getInt("id");
String number = rs.getString("phonenumber");
String address = rs.getString("address");
double balance = rs.getDouble("balance");
//创建User对象
user = new User();
user.setName(name);
user.setId(id);
user.setNumber(number);
user.setAddress(address);
user.setBalance((float) balance);
//装载集合
list.add(user);
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,pstmt,conn);
}
return list;
}//存钱
public static void saveMoney(bank.User u){
u.setOperate("存钱");
System.out.println("请输入您要存入的金额：");
float a = sc.nextFloat();
u.setBalance2(a);
Calendar calendar = Calendar.getInstance(); //知识点23：获取时间
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); //知识点24：更改格式
u.setTime(formatter.format(calendar.getTime()));
Connection conn = null;
PreparedStatement pstmt1 = null;
try{
//获取连接
conn = JDBCUtils.getConnection();
//定义sql
String sql1 = "update user set balance = balance + ? where username = ?";
//-
pstmt1 = conn.prepareStatement(sql1);
//+
pstmt1.setDouble(1,a);
pstmt1.setString(2,u.getName());
pstmt1.executeUpdate();
r_operate(u);
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt1,conn);
}
System.out.println("存钱成功");
}
//取钱
public static void drawMoney(bank.User u){
u.setOperate("取钱");
System.out.println("请输入您要取的金额：");
float a = sc.nextFloat();
u.setBalance2(a);
Calendar calendar = Calendar.getInstance(); //知识点23：获取时间
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); //知识点24：更改格式
u.setTime(formatter.format(calendar.getTime()));
Connection conn = null;
PreparedStatement pstmt1 = null;
try{
//获取连接
conn = JDBCUtils.getConnection();
//定义sql
String sql1 = "update user set balance = balance - ? where username = ?";
//-
pstmt1 = conn.prepareStatement(sql1);
//+
pstmt1.setDouble(1,a);
pstmt1.setString(2,u.getName());
pstmt1.executeUpdate();
r_operate(u);
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt1,conn);
}
System.out.println("取钱成功");
}
//转账
public static void transferMoney(bank.User u){
u.setOperate("转账");
Calendar calendar = Calendar.getInstance(); //知识点23：获取时间
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss"); //知识点24：更改格式
u.setTime(formatter.format(calendar.getTime()));
float money;
System.out.println("请输入您要转账的对方账号：");
String c = sc.next();
System.out.println("请输入您要转账的金额：");
float d = sc.nextFloat();
u.setBalance2(d);
boolean flag = new Bankmanagement().judge(c);
if (flag){
Connection conn = null;
PreparedStatement pstmt1 = null;
PreparedStatement pstmt2 = null;
try{
//获取连接
conn = JDBCUtils.getConnection();
//定义sql
String sql1 = "update user set balance = balance - ? where username = ?";
String sql2 = "update user set balance = balance + ? where username = ?";
//-
pstmt1 = conn.prepareStatement(sql1);
//+
pstmt2 = conn.prepareStatement(sql2);
pstmt1.setDouble(1,d);
pstmt1.setString(2,u.getName());
pstmt2.setDouble(1,d);
pstmt2.setString(2,c);
pstmt1.executeUpdate();
pstmt2.executeUpdate();
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt1,conn);
JDBCUtils.close(pstmt2,null);
}
System.out.println("转账成功");
r_operate(u);
return;
}else {
System.out.println("您输入的帐号不存在请重新输入!");
transferMoney(u);
}
}
public static void r_operate(bank.User u){
Connection conn = null;
Statement stmt = null;
PreparedStatement pstmt = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "insert into record(time,id,username,operate,balance2) values(?,?,?,?,?)";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, u.getTime());
pstmt.setInt(2,u.getId());
pstmt.setString(3,u.getName());
pstmt.setString(4,u.getOperate());
pstmt.setDouble(5,u.getBalance2());
// pstmt.executeUpdate();
//获取执行对象
// stmt = conn.createStatement();
//执行查询
// rs = stmt.executeQuery(sql);
//判断
pstmt.executeUpdate();
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
}
public boolean judge(String username){
if (username == null){
return false;
}
//数据库连接
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from user where username = ?";
//获取执行对象
pstmt = conn.prepareStatement(sql);
//给问号赋值
pstmt.setString(1,username);
//执行查询
rs = pstmt.executeQuery();
//判断
return rs.next();
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,pstmt,conn);
}
return false;
}
//打印清单
public static void print(bank.User u){
ArrayList<User> list = new Bankmanagement().findalluser(u);
System.out.println("信息如下：");
System.out.println("时间 id 用户名 操作 操作金额");
//知识点21：遍历
for (bank.User m : list) {
System.out.println(m.getTime() + " " +m.getId() + " " +m.getName()+" " +m.getOperate() + " " + m.getBalance2());
}
}
public ArrayList<User> findalluser(bank.User u){
//数据库连接
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
ArrayList<User> list = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "select * from record where id = '"+u.getId()+"'";
//获取执行对象
pstmt = conn.prepareStatement(sql);
//执行查询
rs = pstmt.executeQuery();
User user = null;
list = new ArrayList<User>();
//便利
while(rs.next()){
//获取数据
String time = String.valueOf(rs.getTime("time"));
int id = rs.getInt("id");
String name = rs.getString("username");
String operate = rs.getString("operate");
double balance2 = rs.getDouble("balance2");
//创建User对象
user = new User();
user.setTime(time);
user.setId(id);
user.setName(name);
user.setOperate(operate);
user.setBalance2((float) balance2);
//装载集合
list.add(user);
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(rs,pstmt,conn);
}
return list;
}//存钱
//注销账户
public static void cancel(bank.User u){
System.out.println("您是否要注销: Y/N");
String a = sc.next();
//知识点：构造方法
switch(a){
case "Y":
Connection conn = null;
Statement stmt = null;
PreparedStatement pstmt = null;
try{
conn = JDBCUtils.getConnection();
//定义sql语句
String sql = "delete from user where username = ?";
pstmt = conn.prepareStatement(sql);
pstmt.setString(1,u.getName());
//判断
int count =pstmt.executeUpdate();
if (count>0){
System.out.println("注销成功");
menu();
}else{
System.out.println("注销失败,请重试！");
return;
}
}catch (SQLException e){
e.printStackTrace();
}finally {
JDBCUtils.close(pstmt,conn);
}
// }
break;
case "N":
break;
}
}
}
User
package bank;
public class User {
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getNumber() {
return number;
}
public void setNumber(String number) {
this.number = number;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public float getBalance() {
return balance;
}
public void setBalance(float balance) {
this.balance = balance;
}
public String getOperate() {
return operate;
}
public void setOperate(String operate) {
this.operate = operate;
}
public float getBalance2() {
return balance2;
}
public void setBalance2(float balance2) {
this.balance2 = balance2;
}
public String getTime() {
return time;
}
public void setTime(String time) {
this.time = time;
}
public User(String name, String password) {
this.name = name;
this.password = password;
}
public User(String name, int id, String password) {
this.name = name;
this.id = id;
this.password = password;
}
public User() {
}
public User(String name, int id, String number, String address, float balance) {
this.name = name;
this.id = id;
this.number = number;
this.address = address;
this.balance = balance;
}
private String name; //知识点26:声明变量
private int id;
private String number;
private String password;
private String address;
private float balance;
private String operate;
private String time;
@Override
public String toString() {
return "User{" +
"name='" + name + '\'' +
", id=" + id +
", number='" + number + '\'' +
", password='" + password + '\'' +
", address='" + address + '\'' +
", balance=" + balance +
", operate='" + operate + '\'' +
", balance2=" + balance2 +
", time='" + time + '\'' +
'}';
}
private float balance2;
public User(String name, int id, String number, String password, String address, float balance, String operate, float balance2, String time) {
this.name = name;
this.id = id;
this.number = number;
this.password = password;
this.address = address;
this.balance = balance;
this.operate = operate;
this.balance2 = balance2;
this.time = time;
}
public User(String name, int id, float balance, String operate, float balance2, String time) {
this.name = name;
this.id = id;
this.balance = balance;
this.operate = operate;
this.balance2 = balance2;
this.time = time;
}
}
JDBCUtils
package bank;
import javax.lang.model.element.NestingKind;
import java.io.FileReader;
import java.io.IOException;
import java.net.URL;
import java.sql.*;
import java.util.Properties;
/**
* 文件的读取，只需要读取一次即可拿到这些值
*
* **/
public class JDBCUtils {
// private static String url;
// private static String user;
// private static String password;
// private static String driver;
static {
//读取文件资源
try {
// //1.创建Properties集合类
// Properties pro = new Properties();
// //获取src路径下的文件方式-->ClassLoader
// ClassLoader classLoader = JDBCUtils.class.getClassLoader();
// URL res = classLoader.getResource("jdbc.properties");
// String path = res.getPath();
// System.out.println(path);
// //2.加载文件
// pro.load(new FileReader(path));
// //3.获取数据，赋值
// url = pro.getProperty("url");
// user = pro.getProperty("user");
// password = pro.getProperty("password");
// driver = pro.getProperty("driver");
//4.注册驱动
Class.forName("com.mysql.cj.jdbc.Driver");
} catch (ClassNotFoundException e) {
throw new RuntimeException(e);
}
}
public static Connection getConnection() throws SQLException {
return DriverManager.getConnection("jdbc:mysql://localhost:3306/bank","root","gqdqcc21");
}
public static void close(ResultSet rs,Statement stmt, Connection conn){
if (rs !=null){
try{
rs.close();
}catch (SQLException e){
e.printStackTrace();
}
}
if (stmt !=null){
try{
stmt.close();
}catch (SQLException e){
e.printStackTrace();
}
}
if (conn !=null){
try{
conn.close();
}catch (SQLException e){
e.printStackTrace();
}
}
}
public static void close(Statement stmt, Connection conn){
if (stmt !=null){
try{
stmt.close();
}catch (SQLException e){
e.printStackTrace();
}
}
if (conn !=null){
try{
conn.close();
}catch (SQLException e){
e.printStackTrace();
}
}
}
}