JavaWeb项目-----博客系统

一.设计数据库

1.创建数据库

create database if not exists java108_blog_system character set utf8;
drop table if exists user;
drop table if exists blog;

2.创建博客列表

create table blog(
 blogId int primary key auto_increment,
 title varchar(20),
 content varchar(4006),
 userId int,
 postTime datetime
);

3.创建用户列表

create table user(
userId int primary key auto_increment,
username varchar(64) unique,
password varchar(64)
);

4.确认表创建成功

insert into user values(1,"zhangsan","123"),(2,"lisi","123");
insert into blog values(1,"这是我的第一篇博客","从今天开始我要好好写代码",1,"2024-07-14 19:00:00");
insert into blog values(2,"这是我的第二篇博客","从昨天开始我要好好写代码",2,"2024-07-14 19:00:01");
insert into blog values(3,"这是我的第三篇博客","从明天开始我要好好写代码",3,"2024-07-14 19:00:02");

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二.封装数据库

创建包Dao用来放数据库代码
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1.创建Dbuc类

数据库建立连接

package Dao;

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class Dbuc {
    private static DataSource dataSource = null;
    private static DataSource getDataSource(){
        if(dataSource==null){
            synchronized (Dbuc.class){
                if(dataSource==null){
                    dataSource=new MysqlDataSource();
                    ((MysqlDataSource) dataSource).setUrl("jdbc:mysql://127.0.0.1/java108_blog_system?characterEncoding=utf8&useSSL=false");
                    ((MysqlDataSource)dataSource).setUser("root");
//                    ((MysqlDataSource)dataSource).setUser("java108");
                    ((MysqlDataSource)dataSource).setPassword("123456");
                }
            }
        }
        return dataSource;
    }
    public static Connection getConnect() throws SQLException {

      return getDataSource().getConnection();



    }
    public static void close(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet) throws SQLException {
        if(resultSet!=null){
            resultSet.close();
        }
        if(connection!=null){
            connection.close();
        }
        if(preparedStatement!=null){
            preparedStatement.close();
        }
    }

}

2.创建博客类

public class Blog {
    public int blogId;
    public String  title;
    public String content;
    public int  userId;

    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    public Timestamp postTime;

    @Override
    public String toString() {
        return "Blog{" +
                "blogId=" + blogId +
                ", title='" + title + '\'' +
                ", content='" + content + '\'' +
                ", userId=" + userId +
                ", postTime=" + postTime +
                '}';
    }


}

3.创建用户类

package Dao;

public class User {
    public int  userId;
    public String username;
    public String  password;

    @Override
    public String toString() {
        return "User{" +
                "userId=" + userId +
                ", username='" + username + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

4.封装博客增删查改

package Dao;

import javax.xml.transform.Result;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class BlogDao {


    public void insert(Blog blog) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String sql = "insert into blog values(null,?,?,?,now())";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setString(1,blog.title);
        preparedStatement.setString(2,blog.content);
        preparedStatement.setInt(3,blog.userId);
        preparedStatement.executeUpdate();
        Dbuc.close(connection,preparedStatement,null);
    }
    public List<Blog> getBlogs() throws SQLException {

        List<Blog> list1= new ArrayList<>();

        Connection connection = Dbuc.getConnect();


        String sql = "select* from blog order by postTime desc";

        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        ResultSet resultSet= preparedStatement.executeQuery();

        while(resultSet.next()){
            Blog blog = new Blog();
            blog.blogId = resultSet.getInt("blogId");
            blog.title=resultSet.getString("title");
            blog.content=resultSet.getString("content");
            blog.userId=resultSet.getInt("userId");
            blog.postTime=resultSet.getTimestamp("postTime");
            list1.add(blog);
        }
        Dbuc.close(connection,preparedStatement,resultSet);
           return list1;
    }
public Blog getBlog(int blogId) throws SQLException {

    Connection connection = Dbuc.getConnect();
    String sql = "select* from blog where  blogId=?";
    PreparedStatement preparedStatement = connection.prepareStatement(sql);
    preparedStatement.setInt(1,blogId);
    ResultSet resultSet= preparedStatement.executeQuery();
    if(resultSet.next()){
        Blog blog = new Blog();
        blog.blogId = resultSet.getInt("blogId");
        blog.title=resultSet.getString("title");
        blog.content=resultSet.getString("content");
        blog.userId=resultSet.getInt("userId");
        blog.postTime=resultSet.getTimestamp("postTime");
      return blog;
    }
    Dbuc.close(connection,preparedStatement,resultSet);
  return null;
}
public void delete(int blogId) throws SQLException {
    Connection connection = Dbuc.getConnect();
    String sql = "delete from blog where blogId=?";
    PreparedStatement preparedStatement = connection.prepareStatement(sql);
    preparedStatement.setInt(1,blogId);
    preparedStatement.executeUpdate();
    Dbuc.close(connection,preparedStatement,null);
}
}

5.封装用户类增删查改

package Dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class UserDao {
    public User getUserById(int userId) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String  sql = "select* from user where userId=?";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setInt(1,userId);
        ResultSet resultSet = preparedStatement.executeQuery();
        if(resultSet.next()){
            User user = new User();
            user.userId=resultSet.getInt("userId");
            user.password=resultSet.getString("password");
            user.username=resultSet.getString("username");
            return user;
        }
        Dbuc.close(connection,preparedStatement,resultSet);
        return null;
    }
    public User getUserByName(String username) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String  sql = "select* from user where username=?";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setString(1,username);
        ResultSet resultSet = preparedStatement.executeQuery();
        if(resultSet.next()){
            User user = new User();
            user.userId=resultSet.getInt("userId");
            user.password=resultSet.getString("password");
            user.username=resultSet.getString("username");
            return user;
        }
        Dbuc.close(connection,preparedStatement,resultSet);
        return null;
    }
}

三.博客详情页

package api;

import Dao.Blog;
import Dao.BlogDao;
import Dao.User;
import com.fasterxml.jackson.databind.ObjectMapper;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;
import java.util.List;

@WebServlet("/blog")
public class BlogServlet extends HttpServlet {
    private ObjectMapper objectMapper = new ObjectMapper();
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        BlogDao  blogDao = new BlogDao();
        String blogId = req.getParameter("blogId");
        if(blogId==null){
            List<Blog> blogs = null;
            try {
                blogs = blogDao.getBlogs();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            String res = objectMapper.writeValueAsString(blogs);
            resp.setContentType("appliaction/jason;charset=utf8");
            resp.getWriter().write(res);
        }else{
            Blog blog = null;
            try {
                blog = blogDao.getBlog(Integer.parseInt(blogId));
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            String str = objectMapper.writeValueAsString(blog);
            resp.setContentType("application/json;charset=utf8");
            resp.getWriter().write(str);
        }


    }

如果前端没有传入指定id那么展示全部内容，如果传入指定id查询指定用户博客。

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通过抓包观察：

2.检测用户是否登录

如果用户未登录是不能跳转到博客列表的页面

@Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        HttpSession session = req.getSession(false);
        if (session == null) {
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("用户未登录! 无法发布博客!");
            return;
        }

        User user = (User) session.getAttribute("user");
        if (user == null) {
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("用户未登录! 无法发布博客!");
            return;
        }

        req.setCharacterEncoding("utf8");
        String title = req.getParameter("title");
        String content = req.getParameter("content");
        if (title == null || content == null || "".equals(title) || "".equals(content)) {
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("标题或者正文为空");
            return;
        }

        Blog blog = new Blog();

        blog.title=title;
        blog.userId=user.userId;
        blog.content=content;

        BlogDao blogDao = new BlogDao();
        try {
            blogDao.insert(blog);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

        resp.sendRedirect("blog_list.html");
    }

主要功能是处理博客发布相关的操作。首先，它会检查用户是否登录，通过获取用户会话（HttpSession），如果会话不存在或者从会话中获取不到代表用户的User对象，就会向客户端返回“用户未登录! 无法发布博客!”的提示并终止方法执行。如果用户已登录，它会从POST请求中获取博客的标题（title）和内容（content），并且对获取到的标题和内容进行验证，如果标题或者内容为空（null或者空字符串），则向客户端返回“标题或者正文为空”的提示并终止方法。如果标题和内容都有效，它会创建一个Blog对象，将从请求中获取到的标题和内容以及从用户对象中获取到的用户ID设置到Blog对象的属性中。然后通过BlogDao将博客对象插入到数据库中。最后，如果博客插入成功，将客户端重定向到blog_list.html页面，展示博客列表的页面。

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3.用户登录

package api;

import Dao.User;
import Dao.UserDao;
import utils.CloudSmsUtil;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;
@WebServlet("/login")
public class LoginSevlet extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("utf8");
        String usename = req.getParameter("username");
        String password=req.getParameter("password");
        String phone = req.getParameter("phone");
        String code = req.getParameter("code");
        if(usename==null||password==null||"".equals(usename)||"".equals(password)||"".equals(phone)||"".equals(code)){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("传过来数值错误");
            return;
        }
        String inoutCode = CloudSmsUtil.PHONE_CODE_MAP.get(phone);
        if (!code.equals(inoutCode)) {
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("验证码错误");
            return;
        }
        UserDao userDao = new UserDao();
        User user = null;
        try {

            user = userDao.getUserByName(usename);

        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
        if(user==null){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("查无此人");
            return;
        }
        if(!password.equals(user.password)){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("密码错误");
            return;
        }
        HttpSession httpSession = req.getSession(true);
        httpSession.setAttribute("user",user);
        resp.sendRedirect("blog_list.html");
    }

package utils;

import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSONObject;
import com.aliyuncs.DefaultAcsClient;
import com.aliyuncs.IAcsClient;
import com.aliyuncs.dysmsapi.model.v20170525.SendSmsRequest;
import com.aliyuncs.dysmsapi.model.v20170525.SendSmsResponse;
import com.aliyuncs.exceptions.ClientException;
import com.aliyuncs.exceptions.ServerException;
import com.aliyuncs.http.MethodType;
import com.aliyuncs.profile.DefaultProfile;
import com.aliyuncs.profile.IClientProfile;

import java.util.HashMap;
import java.util.Map;

public class CloudSmsUtil {

    private final static String accessKeyId = "LTAI5tEqaD59ckPYDhhxJ3ZF";

    private final static String accessKeySecret = "x6aD71AB7NmKhlayqhGIN1nt44M0TG";

    private final static String showStartNoticeTemplate = "SMS_474960284";

    private final static String signName = "我的学习路";

    /**ali固定配置参数begin*/
    //短信API产品名称
    static final String product="Dysmsapi";
    //短信API产品域名
    static final String domain="dysmsapi.aliyuncs.com";
    /**ali固定配置参数end*/

    public final static Map<String, String> PHONE_CODE_MAP = new HashMap<>();

    public static boolean sendCheckCode(String phone, String code) {
        JSONObject params = new JSONObject();
        params.put("code", code);
        return  aliSmsSendMsg(showStartNoticeTemplate, phone, params);
    }


    private static boolean aliSmsSendMsg(String templateCode, String phone, JSONObject params) {

//		System.out.println("alibaba-phone:" + phone + "-code:" + code);
        System.out.println("配置信息");
        System.out.println("accessKeyId:" + accessKeyId);
        System.out.println("accessKeySecret:" + accessKeySecret);
        System.out.println("signName:" + signName);
        System.out.println("templateCode:" + templateCode);
        try {
            //设置超时时间
            System.setProperty("sun.net.client.defaultConnectTimeout", "10000");
            System.setProperty("sun.net.client.defaultReadTimeout", "10000");
            //初始化ascClient
            IClientProfile profile= DefaultProfile.getProfile("cn-hangzhou", accessKeyId, accessKeySecret);
            DefaultProfile.addEndpoint("cn-hangzhou", "cn-hangzhou", product, domain);
            IAcsClient acsClient=new DefaultAcsClient(profile);
            //组装请求对象
            SendSmsRequest request=new SendSmsRequest();
            //使用post提交
            request.setMethod(MethodType.POST);
            //待发送的手机号
            request.setPhoneNumbers(phone);
            //短信签名
            request.setSignName(signName);
            //短信模板ID
            request.setTemplateCode(templateCode);
            /*
             * 可选:模板中的变量替换JSON串,
             * 如模板内容为"亲爱的${name},您的验证码为${code}"时,
             * 此处的值为{"name":"Tom","code":"1454"}
             *   \  反斜杠为转义字符，使得输出双引号
             */
            request.setTemplateParam(params.toString());
            //可选:outId为提供给业务方扩展字段,最终在短信回执消息中将此值带回给调用者
            //request.setOutId("1454");
            SendSmsResponse response=acsClient.getAcsResponse(request);

            System.out.println(response.getCode() + ":" + response.getMessage());
            if(response.getCode() != null && response.getCode().equals("OK")) {
                //请求成功
                System.out.println("发送成功！");
                return true;
            }else {
                System.out.println(StrUtil.format("发送失败！{}", response.getCode() + ":" + response.getMessage()));
                return false;
            }
        } catch (ServerException e) {
            e.printStackTrace();
            return false;
        } catch (ClientException e) {
            e.printStackTrace();
            return false;
        }
    }
}

package api;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

@WebServlet("/logout")
public class LogouServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        HttpSession httpSession = req.getSession(false);
        if(httpSession==null){
            resp.sendRedirect("login.html");
            return;
        }
        httpSession.removeAttribute("user");
        resp.sendRedirect("login.html");
    }
}

package api;

import Dao.User;
import Dao.UserDao;
import cn.hutool.core.util.RandomUtil;
import utils.CloudSmsUtil;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;

@WebServlet("/sendCode")
public class SendSmsCodeSevlet extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("utf8");
        String phone = req.getParameter("phone");
        String code = RandomUtil.randomNumbers(4);
        boolean b = CloudSmsUtil.sendCheckCode(phone, code);
//        resp.setContentType("application/json;charset=utf8");
        if (b) {
            System.out.println("[发送验证码]-----------------------验证码为："+ code);
            CloudSmsUtil.PHONE_CODE_MAP.put(phone, code);
            resp.getWriter().write("1");
        } else {
            resp.getWriter().write("0");
        }

    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
       doPost(req, resp);
    }
}

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四.新增博客

package Dao;

import javax.xml.transform.Result;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class BlogDao {


    public void insert(Blog blog) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String sql = "insert into blog values(null,?,?,?,now())";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setString(1,blog.title);
        preparedStatement.setString(2,blog.content);
        preparedStatement.setInt(3,blog.userId);
        preparedStatement.executeUpdate();
        Dbuc.close(connection,preparedStatement,null);
    }
    public List<Blog> getBlogs() throws SQLException {

        List<Blog> list1= new ArrayList<>();

        Connection connection = Dbuc.getConnect();


        String sql = "select* from blog order by postTime desc";

        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        ResultSet resultSet= preparedStatement.executeQuery();

        while(resultSet.next()){
            Blog blog = new Blog();
            blog.blogId = resultSet.getInt("blogId");
            blog.title=resultSet.getString("title");
            blog.content=resultSet.getString("content");
            blog.userId=resultSet.getInt("userId");
            blog.postTime=resultSet.getTimestamp("postTime");
            list1.add(blog);
        }
        Dbuc.close(connection,preparedStatement,resultSet);
           return list1;
    }
public Blog getBlog(int blogId) throws SQLException {

    Connection connection = Dbuc.getConnect();
    String sql = "select* from blog where  blogId=?";
    PreparedStatement preparedStatement = connection.prepareStatement(sql);
    preparedStatement.setInt(1,blogId);
    ResultSet resultSet= preparedStatement.executeQuery();
    if(resultSet.next()){
        Blog blog = new Blog();
        blog.blogId = resultSet.getInt("blogId");
        blog.title=resultSet.getString("title");
        blog.content=resultSet.getString("content");
        blog.userId=resultSet.getInt("userId");
        blog.postTime=resultSet.getTimestamp("postTime");
      return blog;
    }
    Dbuc.close(connection,preparedStatement,resultSet);
  return null;
}
public void delete(int blogId) throws SQLException {
    Connection connection = Dbuc.getConnect();
    String sql = "delete from blog where blogId=?";
    PreparedStatement preparedStatement = connection.prepareStatement(sql);
    preparedStatement.setInt(1,blogId);
    preparedStatement.executeUpdate();
    Dbuc.close(connection,preparedStatement,null);
}
}

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五.获取个人ID

package api;

import Dao.Blog;
import Dao.BlogDao;
import Dao.User;
import Dao.UserDao;
import com.fasterxml.jackson.databind.ObjectMapper;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;

@WebServlet("/user")
public class UserServlet extends HttpServlet {
    private ObjectMapper objectMapper = new ObjectMapper();

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String blogId = req.getParameter("blogId");
        if (blogId == null) {

            HttpSession session = req.getSession(false);
            if (session == null) {
                User user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            User user = (User) session.getAttribute("user");
            if (user == null) {
                user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            String respJson = objectMapper.writeValueAsString(user);
            resp.setContentType("application/json; charset=utf8");
            resp.getWriter().write(respJson);
        } else {

            BlogDao blogDao = new BlogDao();
            Blog blog = null;
            try {
                blog = blogDao.getBlog(Integer.parseInt(blogId));
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            if (blog == null) {
                User user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            UserDao userDao = new UserDao();
            User user = null;
            try {
                user = userDao.getUserById(blog.userId);
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            if (user == null) {
                user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            String respJson = objectMapper.writeValueAsString(user);
            resp.setContentType("application/json; charset=utf8");
            resp.getWriter().write(respJson);
        }


    }
}

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六.总效果展示

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七.总代码

1.代码分层

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2.前端代码

!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>博客详情页</title>
    <link rel="stylesheet" href="css/common.css">
    <link rel="stylesheet" href="css/blog_detail.css">

    <!-- 一定要引入 editormd 的依赖, 才能使用这里的方法 -->
    <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
    <link rel="stylesheet" href="editor.md/css/editormd.min.css" />
    <script src="editor.md/lib/marked.min.js"></script>
    <script src="editor.md/lib/prettify.min.js"></script>
    <script src="editor.md/editormd.js"></script>
</head>
<body>
<!-- 导航栏. nav 是 导航 这个词的缩写 -->
<div class="nav">
    <!-- logo -->
    <img src="image/logo2.jpg" alt="">
    <div class="title">我的博客系统</div>
    <!-- 只是一个空白, 用来把后面的链接挤过去 -->
    <!-- 这是一个简单粗暴的写法~~ -->
    <div class="spacer"></div>
    <a href="blog_list.html">主页</a>
    <a href="blog_edit.html">写博客</a>
    <!-- 这里的地址回头再说 -->
    <a href="logout">注销</a>
</div>
<!-- 页面的主体部分 -->
<div class="container">
    <!-- 左侧信息 -->
    <div class="container-left">
        <!-- 这个 div 表示整个用户信息的区域 -->
        <div class="card">
            <!-- 用户的头像 -->
            <img src="image/kun.jpg" alt="">
            <!-- 用户名 -->
            <h3>小新要加油</h3>
            <!-- github 地址 -->
            <a href="https://www.github.com">github 地址</a>
            <!-- 统计信息 -->
            <div class="counter">
                <span>文章</span>
                <span>分类</span>
            </div>
            <div class="counter">
                <span>2</span>
                <span>1</span>
            </div>
        </div>
    </div>

    <!-- 右侧信息 -->
    <div class="container-right">
        <h3>这是我的第一篇博客</h3>
        <div class="date">2023-05-11 20:00:00</div>
        <div class="content">
             <h3></h3>
            <div class="date"></div>
            <div id="content">
            </div>
        </div>
    </div>
    <script src="js/app.js"></script>
    <script>

        function getUrlParam(url, paramName) {
            const reg = new RegExp('(^|&)' + paramName + '=([^&]*)(&|$)', 'i');
            const result = url.slice(url.indexOf('?') + 1).match(reg);
            if (result !== null) {
                return decodeURIComponent(result[2]);
            }
            return null;
        }

        function getBlog(blogId) {
            $.ajax({
                url: 'blog?blogId=' + blogId,
                type: 'get',
                success: function(body) {
                    // body = JSON.parse(body)
                    // 根据拿到的响应数据, 构造页面内容.
                    let h3 = document.querySelector('.container-right h3');
                    h3.innerHTML = body.title;
                    let dateDiv = document.querySelector('.container-right .date');
                    dateDiv.innerHTML = body.postTime;
                    editormd.markdownToHTML('content', { markdown: body.content });
                }
            });
        }

        getBlog(getUrlParam(window.location.href, 'blogId'));

        checkLogin();

        function getUser() {
            $.ajax({
                type: 'get',
                url: 'user' + location.search,
                success: function(body) {
                    // body 就是解析后的 user 对象了.
                    let h3 = document.querySelector('.card h3');
                    h3.innerHTML = body.username;
                }
            })
        }
        getUser();
    </script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>博客编辑页</title>
    <link rel="stylesheet" href="css/common.css">
    <link rel="stylesheet" href="css/blog_edit.css">
    <script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
    <!-- 引入 editor.md 的依赖 -->
    <link rel="stylesheet" href="editor.md/css/editormd.min.css" />
    <script src="editor.md/lib/marked.min.js"></script>
    <script src="editor.md/lib/prettify.min.js"></script>
    <script src="editor.md/editormd.js"></script>
</head>
<body>
<!-- 导航栏. nav 是 导航 这个词的缩写 -->
<div class="nav">
    <!-- logo -->
    <img src="image/logo2.jpg" alt="">
    <div class="title">我的博客系统</div>
    <!-- 只是一个空白, 用来把后面的链接挤过去 -->
    <!-- 这是一个简单粗暴的写法~~ -->
    <div class="spacer"></div>
    <a href="blog_list.html">主页</a>
    <a href="blog_edit.html">写博客</a>
    <!-- 这里的地址回头再说 -->
    <a href="logout">注销</a>
</div>

<!-- 博客编辑页的版心 -->
<div class="blog-edit-container">
    <form action="blog" method="post">
        <!-- 标题编辑区 -->
        <div class="title">
            <input type="text" id="title-input" name="title">
            <input type="submit" id="submit">
        </div>
        <!-- 博客编辑器 -->
        <!-- 把 md 编辑器放到这个 div 中 -->
        <div id="editor">
            <textarea name="content" style="display: none"></textarea>
        </div>
    </form>
</div>

<script src="js/app.js"></script>
<script>
    var editor = editormd("editor", {
        // 这里的尺寸必须在这里设置. 设置样式会被 editormd 自动覆盖掉.
        width: "100%",
        // 设定编辑器高度
        height: "calc(100% - 50px)",
        // 编辑器中的初始内容
        markdown: "# 在这里写下你的留言",
        // 指定 editor.md 依赖的插件路径
        path: "editor.md/lib/"
    });

    checkLogin();
</script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>博客列表页</title>

    <link rel="stylesheet" href="css/common.css">
    <link rel="stylesheet" href="css/blog_list.css">
</head>
<body>
<!-- 导航栏. nav 是 导航 这个词的缩写 -->
<div class="nav">
    <!-- logo -->
    <img src="image/logo2.jpg" alt="">
    <div class="title">我的博客系统</div>
    <!-- 只是一个空白, 用来把后面的链接挤过去 -->
    <!-- 这是一个简单粗暴的写法~~ -->
    <div class="spacer"></div>
    <a href="blog_list.html">主页</a>
    <a href="blog_edit.html">写博客</a>
    <!-- 这里的地址回头再说 -->
    <a href="logout">注销</a>
</div>

<!-- 页面的主体部分 -->
<div class="container">
    <!-- 左侧信息 -->
    <div class="container-left">
        <!-- 这个 div 表示整个用户信息的区域 -->
        <div class="card">
            <!-- 用户的头像 -->
            <img src="image/kun.jpg" alt="">
            <!-- 用户名 -->
            <h3>勇敢的小新</h3>
            <!-- github 地址 -->
            <a href="https://www.github.com">github 地址</a>
            <!-- 统计信息 -->
            <div class="counter">
                <span>文章</span>
                <span>分类</span>
            </div>
            <div class="counter">
                <span>2</span>
                <span>1</span>
            </div>
        </div>
    </div>
    <!-- 右侧信息 -->
    <div class="container-right">
        <!-- <div class="blog">
            <div class="title">我的第一篇博客博客博客博客</div>
            <div class="date">2023-05-11 20:00:00</div>
            <div class="desc">
                从今天起, 我要认真敲代码. Lorem ipsum dolor sit amet consectetur, adipisicing elit. Debitis repellendus voluptatum, reiciendis rem consectetur incidunt aspernatur eveniet excepturi magni quis sint, provident est at et pariatur dolorem aliquid fugit voluptatem.
            </div>
            <a href="blog_detail.html?blogId=1">查看全文 &gt;&gt; </a>
        </div> -->

    </div>
</div>
<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
<script src="js/app.js"></script>
<script>
    // 编写 js 代码.
    // 构造 http 请求, 获取到博客列表数据, 并展示到页面上.
    function getBlogs() {
        $.ajax({
            type: 'get',
            url: 'blog',
            success: function(body) {
                // 就需要根据响应的内容, 构造出 html 片段, 展示到页面上.
                // 由于服务器响应中已经设置了 Content-Type 为 application/json, 此时
                // jQuery 就能够自动的把此处响应的内容解析成 js 对象数组.
                let containter = document.querySelector('.container-right');
                debugger
                for (let blog of JSON.parse(body)) {
                    // 根据当前这个 blog 构造出一个 html 片段.
                    let blogDiv = document.createElement('div');
                    blogDiv.className = 'blog';
                    // 构造标题
                    let titleDiv = document.createElement('div');
                    titleDiv.className = 'title';
                    titleDiv.innerHTML = blog.title;
                    blogDiv.appendChild(titleDiv);
                    // 构造发布时间
                    let dateDiv = document.createElement('div');
                    dateDiv.className = 'date';
                    dateDiv.innerHTML = blog.postTime;
                    blogDiv.appendChild(dateDiv);
                    // 构造摘要信息
                    let descDiv = document.createElement('div');
                    descDiv.className = 'desc';
                    descDiv.innerHTML = blog.content;
                    blogDiv.appendChild(descDiv);
                    // 构造 "查看全文" 按钮
                    let a = document.createElement("a");
                    a.href = 'blog_detail.html?blogId=' + blog.blogId;
                    a.innerHTML = '查看全文 &gt;&gt;';
                    blogDiv.appendChild(a);
                    // 最后把拼好的 blogDiv 添加到 container 的后面
                    containter.appendChild(blogDiv);
                }
            }
        });
    }
    getBlogs();

    checkLogin();
    function getUser() {
        $.ajax({
            type: 'get',
            url: 'user',
            success: function(body) {
                // body 就是解析后的 user 对象了.
                let h3 = document.querySelector('.card h3');
                h3.innerHTML = body.username;
            }
        })
    }
    getUser();

</script>
</body>
</html>

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>博客登录页</title>
    <link rel="stylesheet" href="css/common.css">
    <link rel="stylesheet" href="css/login.css">
</head>
<body>
<!-- 导航栏. nav 是 导航 这个词的缩写 -->
<div class="nav">
    <!-- logo -->
    <img src="image/logo2.jpg" alt="">
    <div class="title">电信ydx的博客系统</div>
    <!-- 只是一个空白, 用来把后面的链接挤过去 -->
    <!-- 这是一个简单粗暴的写法~~ -->
    <div class="spacer"></div>
    <a href="blog_list.html">主页</a>
    <a href="blog_edit.html">写博客</a>
</div>

<!-- 登录页的版心 -->
<div class="login-container">
    <!-- 登录对话框 -->
    <div class="login-dialog">
        <h3>登录</h3>
        <!-- 使用 form 包裹一下下列内容, 便于后续给服务器提交数据 -->
        <form action="login" method="post">
            <div class="row">
                <span>用户名</span>
                <input type="text" id="username" name="username">
            </div>
            <div class="row">
                <span>密码</span>
                <input type="password" id="password" name="password">
            </div>
            <div class="row">
                <span>手机号</span>
                <input type="text" id="phone" name="phone">
                <button id="sendCode">发送验证码</button>
            </div>
            <div class="row" id="phoneCheckCode" style="display: none">
                <span>验证码</span>
                <input type="text" id="code" name="code">
            </div>
            <div class="row" id="sendPhoneCheckCode">

            </div>
            <div class="row">
                <input type="submit" id="submit" value="登录">
            </div>
        </form>
    </div>
</div>
<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
<script src="js/app.js"></script>
<script>
    document.getElementById('sendCode').addEventListener('click', function(event) {
        event.preventDefault();
        // 这里可以添加其他逻辑
        $('#sendCode').on('click', function() {
            var phone = $("#phone").val()
            $.ajax({
                type: 'get',
                url: 'sendCode?phone='+phone,
                success: function(body) {
                    if (body=="0") {
                        alert("发送失败")
                        return
                    } else {
                        alert("发送成功")
                        $("#sendCode").hide()
                        $("#phoneCheckCode").show()
                        return;
                    }

                }
            });
        });
    });
    $(document).ready(function() {
        // 在这里写入需要在页面加载后执行的代码
        console.log('页面已加载完毕！');

    });


</script>
</body>
</html>

3.后端代码

1.api

package api;

import Dao.Blog;
import Dao.BlogDao;
import Dao.User;
import com.fasterxml.jackson.databind.ObjectMapper;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;
import java.util.List;

@WebServlet("/blog")
public class BlogServlet extends HttpServlet {
    private ObjectMapper objectMapper = new ObjectMapper();
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        BlogDao  blogDao = new BlogDao();
        String blogId = req.getParameter("blogId");
        if(blogId==null){
            List<Blog> blogs = null;
            try {
                blogs = blogDao.getBlogs();
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            String res = objectMapper.writeValueAsString(blogs);
            resp.setContentType("appliaction/jason;charset=utf8");
            resp.getWriter().write(res);
        }else{
            Blog blog = null;
            try {
                blog = blogDao.getBlog(Integer.parseInt(blogId));
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            String str = objectMapper.writeValueAsString(blog);
            resp.setContentType("application/json;charset=utf8");
            resp.getWriter().write(str);
        }


    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        HttpSession session = req.getSession(false);
        if (session == null) {
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("用户未登录! 无法发布博客!");
            return;
        }

        User user = (User) session.getAttribute("user");
        if (user == null) {
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("用户未登录! 无法发布博客!");
            return;
        }

        req.setCharacterEncoding("utf8");
        String title = req.getParameter("title");
        String content = req.getParameter("content");
        if (title == null || content == null || "".equals(title) || "".equals(content)) {
            resp.setContentType("text/html; charset=utf8");
            resp.getWriter().write("标题或者正文为空");
            return;
        }

        Blog blog = new Blog();

        blog.title=title;
        blog.userId=user.userId;
        blog.content=content;

        BlogDao blogDao = new BlogDao();
        try {
            blogDao.insert(blog);
        } catch (SQLException e) {
            throw new RuntimeException(e);
        }

        resp.sendRedirect("blog_list.html");
    }
}

package api;

import Dao.User;
import Dao.UserDao;
import utils.CloudSmsUtil;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;
@WebServlet("/login")
public class LoginSevlet extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("utf8");
        String usename = req.getParameter("username");
        String password=req.getParameter("password");
        String phone = req.getParameter("phone");
        String code = req.getParameter("code");
        if(usename==null||password==null||"".equals(usename)||"".equals(password)||"".equals(phone)||"".equals(code)){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("传过来数值错误");
            return;
        }
        String inoutCode = CloudSmsUtil.PHONE_CODE_MAP.get(phone);
        if (!code.equals(inoutCode)) {
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("验证码错误");
            return;
        }
        UserDao userDao = new UserDao();
        User user = null;
        try {

            user = userDao.getUserByName(usename);

        } catch (SQLException e) {
            throw new RuntimeException(e);
        }
        if(user==null){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("查无此人");
            return;
        }
        if(!password.equals(user.password)){
            resp.setContentType("text/html;charset=utf8");
            resp.getWriter().write("密码错误");
            return;
        }
        HttpSession httpSession = req.getSession(true);
        httpSession.setAttribute("user",user);
        resp.sendRedirect("blog_list.html");
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        HttpSession httpSession =req.getSession(false);
        if(httpSession==null){
            resp.setStatus(403);
            return;
        }
        User user =(User)httpSession.getAttribute("user");
        resp.setStatus(200);
    }
}

package api;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;

@WebServlet("/logout")
public class LogouServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        HttpSession httpSession = req.getSession(false);
        if(httpSession==null){
            resp.sendRedirect("login.html");
            return;
        }
        httpSession.removeAttribute("user");
        resp.sendRedirect("login.html");
    }
}

package api;

import Dao.User;
import Dao.UserDao;
import cn.hutool.core.util.RandomUtil;
import utils.CloudSmsUtil;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;

@WebServlet("/sendCode")
public class SendSmsCodeSevlet extends HttpServlet {
    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        req.setCharacterEncoding("utf8");
        String phone = req.getParameter("phone");
        String code = RandomUtil.randomNumbers(4);
        boolean b = CloudSmsUtil.sendCheckCode(phone, code);
//        resp.setContentType("application/json;charset=utf8");
        if (b) {
            System.out.println("[发送验证码]-----------------------验证码为："+ code);
            CloudSmsUtil.PHONE_CODE_MAP.put(phone, code);
            resp.getWriter().write("1");
        } else {
            resp.getWriter().write("0");
        }

    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
       doPost(req, resp);
    }
}

package api;

import Dao.Blog;
import Dao.BlogDao;
import Dao.User;
import Dao.UserDao;
import com.fasterxml.jackson.databind.ObjectMapper;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.SQLException;

@WebServlet("/user")
public class UserServlet extends HttpServlet {
    private ObjectMapper objectMapper = new ObjectMapper();

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String blogId = req.getParameter("blogId");
        if (blogId == null) {

            HttpSession session = req.getSession(false);
            if (session == null) {
                User user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            User user = (User) session.getAttribute("user");
            if (user == null) {
                user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            String respJson = objectMapper.writeValueAsString(user);
            resp.setContentType("application/json; charset=utf8");
            resp.getWriter().write(respJson);
        } else {

            BlogDao blogDao = new BlogDao();
            Blog blog = null;
            try {
                blog = blogDao.getBlog(Integer.parseInt(blogId));
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            if (blog == null) {
                User user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            UserDao userDao = new UserDao();
            User user = null;
            try {
                user = userDao.getUserById(blog.userId);
            } catch (SQLException e) {
                throw new RuntimeException(e);
            }
            if (user == null) {
                user = new User();
                String respJson = objectMapper.writeValueAsString(user);
                resp.setContentType("application/json; charset=utf8");
                resp.getWriter().write(respJson);
                return;
            }
            String respJson = objectMapper.writeValueAsString(user);
            resp.setContentType("application/json; charset=utf8");
            resp.getWriter().write(respJson);
        }


    }
}

2.Dao

import com.fasterxml.jackson.annotation.JsonFormat;

import java.sql.Timestamp;

public class Blog {
    public int blogId;
    public String  title;
    public String content;
    public int  userId;

    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    public Timestamp postTime;

    @Override
    public String toString() {
        return "Blog{" +
                "blogId=" + blogId +
                ", title='" + title + '\'' +
                ", content='" + content + '\'' +
                ", userId=" + userId +
                ", postTime=" + postTime +
                '}';
    }


}

package Dao;

import javax.xml.transform.Result;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

public class BlogDao {


    public void insert(Blog blog) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String sql = "insert into blog values(null,?,?,?,now())";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setString(1,blog.title);
        preparedStatement.setString(2,blog.content);
        preparedStatement.setInt(3,blog.userId);
        preparedStatement.executeUpdate();
        Dbuc.close(connection,preparedStatement,null);
    }
    public List<Blog> getBlogs() throws SQLException {

        List<Blog> list1= new ArrayList<>();

        Connection connection = Dbuc.getConnect();


        String sql = "select* from blog order by postTime desc";

        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        ResultSet resultSet= preparedStatement.executeQuery();

        while(resultSet.next()){
            Blog blog = new Blog();
            blog.blogId = resultSet.getInt("blogId");
            blog.title=resultSet.getString("title");
            blog.content=resultSet.getString("content");
            blog.userId=resultSet.getInt("userId");
            blog.postTime=resultSet.getTimestamp("postTime");
            list1.add(blog);
        }
        Dbuc.close(connection,preparedStatement,resultSet);
           return list1;
    }
public Blog getBlog(int blogId) throws SQLException {

    Connection connection = Dbuc.getConnect();
    String sql = "select* from blog where  blogId=?";
    PreparedStatement preparedStatement = connection.prepareStatement(sql);
    preparedStatement.setInt(1,blogId);
    ResultSet resultSet= preparedStatement.executeQuery();
    if(resultSet.next()){
        Blog blog = new Blog();
        blog.blogId = resultSet.getInt("blogId");
        blog.title=resultSet.getString("title");
        blog.content=resultSet.getString("content");
        blog.userId=resultSet.getInt("userId");
        blog.postTime=resultSet.getTimestamp("postTime");
      return blog;
    }
    Dbuc.close(connection,preparedStatement,resultSet);
  return null;
}
public void delete(int blogId) throws SQLException {
    Connection connection = Dbuc.getConnect();
    String sql = "delete from blog where blogId=?";
    PreparedStatement preparedStatement = connection.prepareStatement(sql);
    preparedStatement.setInt(1,blogId);
    preparedStatement.executeUpdate();
    Dbuc.close(connection,preparedStatement,null);
}
}

package Dao;

import com.mysql.jdbc.jdbc2.optional.MysqlDataSource;

import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class Dbuc {
    private static DataSource dataSource = null;
    private static DataSource getDataSource(){
        if(dataSource==null){
            synchronized (Dbuc.class){
                if(dataSource==null){
                    dataSource=new MysqlDataSource();
                    ((MysqlDataSource) dataSource).setUrl("jdbc:mysql://127.0.0.1/java108_blog_system?characterEncoding=utf8&useSSL=false");
                    ((MysqlDataSource)dataSource).setUser("root");
//                    ((MysqlDataSource)dataSource).setUser("java108");
                    ((MysqlDataSource)dataSource).setPassword("123456");
                }
            }
        }
        return dataSource;
    }
    public static Connection getConnect() throws SQLException {

      return getDataSource().getConnection();



    }
    public static void close(Connection connection, PreparedStatement preparedStatement, ResultSet resultSet) throws SQLException {
        if(resultSet!=null){
            resultSet.close();
        }
        if(connection!=null){
            connection.close();
        }
        if(preparedStatement!=null){
            preparedStatement.close();
        }
    }

}

package Dao;

public class User {
    public int  userId;
    public String username;
    public String  password;

    @Override
    public String toString() {
        return "User{" +
                "userId=" + userId +
                ", username='" + username + '\'' +
                ", password='" + password + '\'' +
                '}';
    }
}

package Dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

public class UserDao {
    public User getUserById(int userId) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String  sql = "select* from user where userId=?";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setInt(1,userId);
        ResultSet resultSet = preparedStatement.executeQuery();
        if(resultSet.next()){
            User user = new User();
            user.userId=resultSet.getInt("userId");
            user.password=resultSet.getString("password");
            user.username=resultSet.getString("username");
            return user;
        }
        Dbuc.close(connection,preparedStatement,resultSet);
        return null;
    }
    public User getUserByName(String username) throws SQLException {
        Connection connection = Dbuc.getConnect();
        String  sql = "select* from user where username=?";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        preparedStatement.setString(1,username);
        ResultSet resultSet = preparedStatement.executeQuery();
        if(resultSet.next()){
            User user = new User();
            user.userId=resultSet.getInt("userId");
            user.password=resultSet.getString("password");
            user.username=resultSet.getString("username");
            return user;
        }
        Dbuc.close(connection,preparedStatement,resultSet);
        return null;
    }
}

3.utils

package utils;

import cn.hutool.core.util.StrUtil;
import com.alibaba.fastjson.JSONObject;
import com.aliyuncs.DefaultAcsClient;
import com.aliyuncs.IAcsClient;
import com.aliyuncs.dysmsapi.model.v20170525.SendSmsRequest;
import com.aliyuncs.dysmsapi.model.v20170525.SendSmsResponse;
import com.aliyuncs.exceptions.ClientException;
import com.aliyuncs.exceptions.ServerException;
import com.aliyuncs.http.MethodType;
import com.aliyuncs.profile.DefaultProfile;
import com.aliyuncs.profile.IClientProfile;

import java.util.HashMap;
import java.util.Map;

public class CloudSmsUtil {

    private final static String accessKeyId = "LTAI5tEqaD59ckPYDhhxJ3ZF";

    private final static String accessKeySecret = "x6aD71AB7NmKhlayqhGIN1nt44M0TG";

    private final static String showStartNoticeTemplate = "SMS_474960284";

    private final static String signName = "我的学习路";

    /**ali固定配置参数begin*/
    //短信API产品名称
    static final String product="Dysmsapi";
    //短信API产品域名
    static final String domain="dysmsapi.aliyuncs.com";
    /**ali固定配置参数end*/

    public final static Map<String, String> PHONE_CODE_MAP = new HashMap<>();

    public static boolean sendCheckCode(String phone, String code) {
        JSONObject params = new JSONObject();
        params.put("code", code);
        return  aliSmsSendMsg(showStartNoticeTemplate, phone, params);
    }


    private static boolean aliSmsSendMsg(String templateCode, String phone, JSONObject params) {

//		System.out.println("alibaba-phone:" + phone + "-code:" + code);
        System.out.println("配置信息");
        System.out.println("accessKeyId:" + accessKeyId);
        System.out.println("accessKeySecret:" + accessKeySecret);
        System.out.println("signName:" + signName);
        System.out.println("templateCode:" + templateCode);
        try {
            //设置超时时间
            System.setProperty("sun.net.client.defaultConnectTimeout", "10000");
            System.setProperty("sun.net.client.defaultReadTimeout", "10000");
            //初始化ascClient
            IClientProfile profile= DefaultProfile.getProfile("cn-hangzhou", accessKeyId, accessKeySecret);
            DefaultProfile.addEndpoint("cn-hangzhou", "cn-hangzhou", product, domain);
            IAcsClient acsClient=new DefaultAcsClient(profile);
            //组装请求对象
            SendSmsRequest request=new SendSmsRequest();
            //使用post提交
            request.setMethod(MethodType.POST);
            //待发送的手机号
            request.setPhoneNumbers(phone);
            //短信签名
            request.setSignName(signName);
            //短信模板ID
            request.setTemplateCode(templateCode);
            /*
             * 可选:模板中的变量替换JSON串,
             * 如模板内容为"亲爱的${name},您的验证码为${code}"时,
             * 此处的值为{"name":"Tom","code":"1454"}
             *   \  反斜杠为转义字符，使得输出双引号
             */
            request.setTemplateParam(params.toString());
            //可选:outId为提供给业务方扩展字段,最终在短信回执消息中将此值带回给调用者
            //request.setOutId("1454");
            SendSmsResponse response=acsClient.getAcsResponse(request);

            System.out.println(response.getCode() + ":" + response.getMessage());
            if(response.getCode() != null && response.getCode().equals("OK")) {
                //请求成功
                System.out.println("发送成功！");
                return true;
            }else {
                System.out.println(StrUtil.format("发送失败！{}", response.getCode() + ":" + response.getMessage()));
                return false;
            }
        } catch (ServerException e) {
            e.printStackTrace();
            return false;
        } catch (ClientException e) {
            e.printStackTrace();
            return false;
        }
    }
}