JDBC操作数据库(增删改查,注册登录)

import java.sql.Connection;

import java.sql.PreparedStatement;

import java.sql.ResultSet;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.Scanner;

/**

* @author 清澈见底的疯子

*

*/

public class UserServer {

static Scanner sc = new Scanner(System.in);

static Connection conn = null;

//conn = DBUtil.getConnection();

public static void cd() {

System.out.println(" 欢迎登录学生信息管理系统");

System.out.println("-------1 注册----");

System.out.println("-------2 登录----");

System.out.println("-------3 查询----");

System.out.println("-------4 修改----");

System.out.println("-------5 删除----");

System.out.println("-------0 退出----");

}

public static void main(String[] args) {

while(true){

cd();

System.out.println("开始，输入0退出");

int command;

do {

System.out.println("请输入选择的功能：1-5");

command = sc.nextInt();

} while (command!=0 &&command != 1 && command != 2 && command != 3 && command!=4&&command!=5);

switch (command) {

case 1:

register();

break;

case 2:

login();

break;

case 3:

query();

break;

case 4:

modify();

break;

case 5:

delete();

break;

case 0:

System.exit(0);

}

}

}

private static void delete() {

@SuppressWarnings("resource")

Scanner scan = new Scanner(System.in);

System.out.println("请输入要删除的用户名");

String username = scan.nextLine();

System.out.println("请输入此用户ID");

String id = scan.nextLine();

try{

conn = DBUtil.getConnection();

String sql = "delete from StudentInfo where username=? and id=?";

PreparedStatement ps = conn.prepareStatement(sql);

ps.setString(1, username);

ps.setString(2, id);

int n = ps.executeUpdate();

if(n!=0){

System.out.println("信息删除完毕");

}else{

System.out.println("删除失败！");

}

}catch(Exception e){

e.printStackTrace();

}finally{

if(conn != null){

try{

conn.close();

}catch(SQLException e){

e.printStackTrace();

}

}

}

}

private static void modify() {

@SuppressWarnings("resource")

Scanner scan = new Scanner(System.in);

System.out.println("请输入用户名：");

String username = scan.nextLine();

System.out.println("请输入新密码：");

String password = scan.nextLine();

System.out.println("请输入性别:");

String sex = scan.nextLine();

System.out.println("请输入班级:");

String grade = scan.nextLine();

System.out.println("请输入邮箱：");

String email = scan.nextLine();

String check = "^([a-z0-9A-Z]+[-|_|\\.]?)+[a-z0-9A-Z]@([a-z0-9A-Z]+(-[a-z0-9A-Z]+)?\\.)+[a-zA-Z]{2,}$";

System.out.println(email.matches(check));

while (!email.matches(check)) {

System.out.println("邮箱格式错误，请重新输入:");

email = scan.nextLine();

System.out.println(email.matches(check));

}

try{

conn = DBUtil.getConnection();

String sql = "Update StudentInfo SET password=?,email=?,sex=?,grade=? WHERE username=?";

PreparedStatement ps = conn.prepareStatement(sql);

ps.setString(1, password);

ps.setString(2, email);

ps.setString(3, sex);

ps.setString(4, grade);

ps.setString(5, username);

int n = ps.executeUpdate();

if(n!=0){

System.out.println("信息修改完毕");

}else{

System.out.println("修改失败！");

}

}catch(Exception e){

e.printStackTrace();

}finally{

if(conn != null){

try{

conn.close();

}catch(SQLException e){

e.printStackTrace();

}

}

}

}

private static void query() {

@SuppressWarnings("resource")

Scanner scan = new Scanner(System.in);

System.out.println("请输入您要查找的学生姓名:");

String username = scan.nextLine();

try{

conn = DBUtil.getConnection();

Statement state = conn.createStatement();

String sql = "SELECT username ,id,email,sex,grade from StudentInfo where username="+"'"+username+"'";

ResultSet rs = state.executeQuery(sql);

if(rs.next()){

System.out.println("信息如下:"+"\n"+"姓名:"+username+","+"班级:"+rs.getString("grade")+"ID:"+rs.getInt("id")+","+"性别:"+rs.getString("sex")+"邮箱:"+rs.getString("email"));

}else{

System.out.println("查无此人！");

}

}catch(Exception e){

e.printStackTrace();

}finally{

if(conn != null){

try{

conn.close();

}catch(SQLException e){

e.printStackTrace();

}

}

}

}

private static void login() {

@SuppressWarnings("resource")

Scanner scan = new Scanner(System.in);

System.out.println("欢迎登录！");

System.out.println("请输入用户名：");

String username = scan.nextLine();

System.out.println("请输入密码");

int password = Integer.parseInt(scan.nextLine());

try{

conn = DBUtil.getConnection();

Statement state = conn.createStatement();

String sql = "SELECT username ,password,account from userinfo_fancq where username="+"'"+username+"'"+ " and password="+password;

ResultSet rs = state.executeQuery(sql);

if(rs.next()){

System.out.println("您好"+username+","+"欢迎登录学生管理系统!");

}else{

System.out.println("用户名或密码不正确！");

}

}catch(Exception e){

e.printStackTrace();

}finally{

if(conn != null){

try{

conn.close();

}catch(SQLException e){

e.printStackTrace();

}

}

}

}

@SuppressWarnings("resource")

private static void register() {

Scanner scan = new Scanner(System.in);

System.out.println("欢迎注册！");

System.out.println("请输入用户名：");

String username = scan.nextLine();

System.out.println("请输入密码");

String password = scan.nextLine();

System.out.println("请输入性别:");

String sex = scan.nextLine();

System.out.println("请输入班级:");

String grade = scan.nextLine();

System.out.println("请输入邮箱");

String email = scan.nextLine();

String check = "^([a-z0-9A-Z]+[-|_|\\.]?)+[a-z0-9A-Z]@([a-z0-9A-Z]+(-[a-z0-9A-Z]+)?\\.)+[a-zA-Z]{2,}$";

System.out.println(email.matches(check));

while (!email.matches(check)) {

System.out.println("邮箱格式错误，请重新输入:");

email = scan.nextLine();

System.out.println(email.matches(check));

}

try{

conn = DBUtil.getConnection();

Statement state = conn.createStatement();

String sql = "INSERT INTO StudentInfo ( id,username,password,email,sex,grade ) VALUES"+

" ( seq_id_S.NEXTVAL"+",'"+username+"','"+password+"','"+email+"',"+"'"+sex+"',"+"'"+grade+" )";

int rs = state.executeUpdate(sql);

if(rs==1 ){

System.out.println("恭喜"+username+","+"注册成功");

}else{

System.out.println("请重新注册");

}

}catch(Exception e){

e.printStackTrace();

}finally{

if(conn != null){

try{

conn.close();

}catch(SQLException e){

e.printStackTrace();

}

}

}

}

}

DBUtil代码:

import java.io.FileInputStream;

import java.sql.Connection;

//import java.sql.DriverManager;

import java.util.Properties;

import org.apache.commons.dbcp.BasicDataSource;

public class DBUtil {

//DBCP 连接池

private static BasicDataSource ds;

static{

try {

//读取配置文件

//java.util.Properties用来读取配置文件

Properties prop = new Properties();

//通过文件流读取并解析配置文件内容

prop.load(

new FileInputStream("config.properties")

);

String driverName = prop.getProperty("driverName");

String url = prop.getProperty("url");

String username = prop.getProperty("username");

String password = prop.getProperty("password");

//最大连接数

int maxActive = Integer.parseInt(

prop.getProperty("maxActive")

);

//最大等待时间

int maxWait = Integer.parseInt(

prop.getProperty("maxWait")

);

ds = new BasicDataSource();

ds.setDriverClassName(driverName);

ds.setUrl(url);

ds.setUsername(username);

ds.setPassword(password);

//连接池中的最大连接数

ds.setMaxActive(maxActive);

//最大等待时间 getConnection时有效

ds.setMaxWait(maxWait);

} catch (Exception e) {

e.printStackTrace();

}

}

public static Connection getConnection()throws Exception{

try {

return ds.getConnection();

}catch(Exception e){

System.out.println("连接数据库异常");

throw e;

}

}

public static void close(Connection conn){

if(conn != null){

try{

conn.close();

}catch(Exception e){

e.printStackTrace();

}

}

}

public static void rollback(Connection conn){

if(conn != null){

try{

conn.rollback();

}catch(Exception e){

e.printStackTrace();

}

}

}

}