1. 项目设计

前端使用 HTML+CSS+JavaScript+JQuery
后端使用 Spring MVC+Spring Boot+MyBatis

2. 效果展示

3. 创建项目并配置文件

1.1 创建 Spring 项目

1.2 配置文件

application.properties 配置内容

spring.profiles.active=dev

application-dev.properties 配置内容

spring.datasource.url=jdbc:mysql://localhost:3306/MyBlogSystem?characterEncoding=utf8&useSSL=true
spring.datasource.username=root
spring.datasource.password=0000
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver

mybatis.mapper-locations=classpath:mapper/**Mapper.xml

4. 数据库实现用户和博客管理

4.1 设计数据库

这里博客系统, 是一个用户表和博客表,
用户一般分为:

用户Id (每个人一个且互不相同)
用户名 (每个人的用户名不相同)
密码
用户头像(暂不实现)
用户马云地址(暂不实现)

博客一般分为:

博客Id (每篇博客一个且互不相同)
标题
正文
创建时间
修改时间 (这里没用到, 自己想加也可以)
用户Id (可以设置一个外键,这里没设置)

create database if not exists MyBlogSystem;

use MyBlogSystem;

drop table if exists blog;

-- 创建一个博客表
create table blog (
    blogId int primary key auto_increment,
    title varchar(1024),
    content mediumtext,
    postTime datetime,
    userId int
);

drop table if exists user;

-- 创建一个用户信息表
create table user (
    userId int primary key auto_increment,
    username varchar(128) unique,
    password varchar(128)
);

4.2 使用 MyBatis 操作数据库

在 resources 下创建一个 mapper 包. 包下创建 UserMapper.xml 和
BlogMapper.xml

BlogMapper.xml 里是对博客表的数据库操作
UserMapper.xml 里是对用户表的数据库操作

UserMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.demo.mapper.UserMapper">
    <!--  注册一个用户  -->
    <insert id="addUser" keyProperty="userId" keyColumn="userId">
        insert into user(username password) values (#{username}, #{password})
    </insert>

    <!--  通过用户名查找用户信息  -->
    <select id="selectByName" resultType="com.example.demo.model.User">
        select * from user where username = #{username}
    </select>

    <!--  通过用户Id查找用户信息  -->
    <select id="selectById" resultType="com.example.demo.model.User">
        select * from user where userId = #{userId}
    </select>
</mapper>

BlogMapper.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.demo.mapper.BlogMapper">
    <!--  查找当前所有的文章  -->
    <select id="getAllBlog" resultType="com.example.demo.model.Blog">
        select * from blog
    </select>

    <!--  通过博客id查找所有的文章  -->
    <select id="getBlogByBid" resultType="com.example.demo.model.Blog">
        select * from blog where blogId = #{blogId}
    </select>

    <!--  发布一篇博客  -->
    <insert id="postBlog" keyColumn="userId" keyProperty="userId">
        insert into blog(title,content,postTime,userId) values(#{title},#{content},#{postTime},#{userId})
    </insert>

    <!--  删除一篇博客  -->
    <delete id="deleteBlog">
        delete from blog where blogId = #{blogId}
    </delete>

    <!--  更新一篇博客  -->
    <update id="updateBlog">
        update blog set content = #{content},title = #{title} where blogId = #{blogId}
    </update>

    <!--  根据当前用户Id获取所有的博客  -->
    <select id="getAllBlogById" resultType="com.example.demo.model.Blog">
        select * from blog where userId = #{userId}
    </select>
</mapper>

User 实体类和 Blog 实体类

在 model 包下创建 User 类和 Blog 类

User 类

@Data
public class User {
    public int userId;
    public String username;
    public String password;
}

Blog 类

@Data
public class Blog {
    public int blogId;
    public String title;
    public String content;
    public Timestamp postTime;
    public int userId;
}

UserMapper 接口和 BlogMapper 接口

在 mapper 包下创建 UserMapper 和 BlogMapper 接口

UserMapper

@Mapper
public interface UserMapper {
    void addUser(User user);

    User selectByName(String username);

    User selectById(Integer userId);
}

BlogMapper

@Mapper
public interface BlogMapper {
    List<Blog> getAllBlog();
    
    Blog getBlogByBid(Integer blogId);
    
    void postBlog(Blog blog);
    
    void deleteBlog(Integer blogId);
    
    void updateBlog(Blog blog);
    
    List<Blog> getAllBlogById();
}

UserService 类和 BlogService 类

service 包下创建 UserService类 和 BlogService类
UserService

@Service
public class UserService {
    @Resource
    private UserMapper userMapper;

    public void addUser(User user){
        userMapper.addUser(user);
    }

    public User selectByName(String username){
        return userMapper.selectByName(username);
    }

    public User selectById(Integer userId){
        return userMapper.selectById(userId);
    }
}

BlogService

@Service
public class BlogService {
    @Resource
    private BlogMapper blogMapper;

    public List<Blog> getAllBlog(){
        return blogMapper.getAllBlog();
    }

    public Blog getBlogByBid(Integer blogId){
        return blogMapper.getBlogByBid(blogId);
    }

    public void postBlog(Blog blog) {
        blogMapper.postBlog(blog);
    }

    public void deleteBlog(Integer blogId){
        blogMapper.deleteBlog(blogId);
    }

    public void updateBlog(Blog blog){
        blogMapper.updateBlog(blog);
    }

    public List<Blog> getAllBlogById(){
        return blogMapper.getAllBlogById();
    }
}

5. 前后端交互接口设计

交互1

交互2

交互3

交互4

交互5

交互6

交互7

交互8

交互9

交互10

交互11

6. 导入前端代码

导入前端代码到 resources 的 static下

具体代码查看文章博客系统前端界面
https://wangzhi430.blog.csdn.net/article/details/124649884

7. 实现博客主页

这里的交互接口是 交互6

7.1 实现后端代码

@RestController
public class IndexController {
    @Autowired
    private BlogService blogService;

    @RequestMapping("/index")
    public List<Blog> getAllBlog() {
        return blogService.getAllBlog();
    }
}

7.2 实现前端代码

$.ajax({
            url: "index",
            method: "GET",
            success: function(data,status) {
                buildBlogs(data);
            }
        })
        
        function buildBlogs(blogs){
            let rightDiv = document.querySelector('.right');
            for(let blog of blogs){
                let blogDiv = document.createElement('div');
                blogDiv.className = 'article';
                // 创建 title
                let h2 = document.createElement('h2');
                h2.className = 'title';
                h2.innerHTML = blog.title;
                blogDiv.appendChild(h2);
                // 创建 postTime
                let postTime = document.createElement('span');
                postTime.className = 'date';
                postTime.innerHTML = DateFormat(blog.postTime);
                blogDiv.appendChild(postTime);
                // 创建 content
                let content = document.createElement('div');
                content.className = 'desc';
                content.innerHTML = blog.content;
                blogDiv.appendChild(content);
                // 创建 详情页的超链接
                let detailA = document.createElement('a');
                detailA.className = 'more';
                detailA.href = 'art.html?blogId=' + blog.blogId;
                detailA.innerHTML = '查看全文&gt;&gt;';
                blogDiv.appendChild(detailA);
                // 加入到 right 中
                rightDiv.appendChild(blogDiv);
            }
        }

        // 把毫秒级时间戳转化成格式化日期
        function DateFormat(timeStampMS) {
            var date = new Date(timeStampMS);
 
            var year = date.getFullYear(),
                month = date.getMonth()+1,//月份是从0开始的
                day = date.getDate(),
                hour = date.getHours(),
                min = date.getMinutes(),
                sec = date.getSeconds();
            var newTime = year + '-' +
                        (month < 10? '0' + month : month) + '-' +
                        (day < 10? '0' + day : day) + ' ' +
                        (hour < 10? '0' + hour : hour) + ':' +
                        (min < 10? '0' + min : min) + ':' +
                        (sec < 10? '0' + sec : sec);
        
            return newTime;
        }

7.3 测试代码

7.4 解决页面内容太多超出当前浏览器

7.5 解决页面顺序不是按最新时间排序

在BlogMapper.xml中修改当前sql语句.

7.6 解决内容太多, 导致显示的时候占位太多.

7.7 再次测试代码

8. 实现博客详情页

这里的交互是 交互5

8.1 实现后端代码

根据当前blogId来获取文章, 要判断blogId是否合法, 是否存在当前blogId的文章
这里使用, message来判断, 返回的message不为空就表示异常.

@RestController
public class DetailsController {
    @Autowired
    private BlogService blogService;

    @RequestMapping("/details")
    public Object ShowBlog(Integer blogId) {
        HashMap<String,Object> map = new HashMap<>();
        if (blogId == null || blogId < 1) {
            map.put("message","blogId异常!");
            return map;
        }
        Blog blog = blogService.getBlogByBid(blogId);
        if (blog == null) {
            map.put("message","不存在当前blogId的文章");
            return map;
        }
        return blog;
    }
}

8.2 实现前端代码

$.ajax({
            url: "details"+location.search,
            method: "GET",
            success: function(data,status) {
                if(data.message == null) {
                    buildBlog(data);
                } else {
                    alert(data.message);
                    location.assign("home.html");
                }
            }
        })

        function buildBlog(blog){
            // 1. 更新 title
            let titleDiv = document.querySelector('.title');
            titleDiv.innerHTML = blog.title;
            // 2. 更新 postTime
            let postTime = document.querySelector('.date');
            postTime.innerHTML = DateFormat(blog.postTime);
            editormd.markdownToHTML('content', {markdown: blog.content});
            }

            // 把毫秒级时间戳转化成格式化日期
            function DateFormat(timeStampMS) {
            var date = new Date(timeStampMS);

            var year = date.getFullYear(),
                month = date.getMonth()+1,//月份是从0开始的
                day = date.getDate(),
                hour = date.getHours(),
                min = date.getMinutes(),
                sec = date.getSeconds();
            var newTime = year + '-' +
                        (month < 10? '0' + month : month) + '-' +
                        (day < 10? '0' + day : day) + ' ' +
                        (hour < 10? '0' + hour : hour) + ':' +
                        (min < 10? '0' + min : min) + ':' +
                        (sec < 10? '0' + sec : sec);

            return newTime;
            }

8.3 测试代码

8.4 这里展示为markdown语法的正文

展示为 markdown 语法的正文.
注意这里的几段代码

这里还需要导入依赖包

9. 实现博客登录界面

这里的交互是 交互8

9.1 实现后端代码

这里要根据前端穿过来的 json 格式数据进行判断
判断当前是否存在用户, 以及当前用户密码是否正确
登录成功之后, 要创建一个session

@RestController
public class LoginController {
    @Autowired
    private UserService userService;

    @RequestMapping("/login")
    public Object userLogin(@RequestBody User user, HttpServletRequest request) {
        HashMap<String,Object> map = new HashMap<>();
        if (user == null) {
            map.put("message","当前还没有输入用户名和密码,登录失败!");
            return map;
        }
        User user1 = userService.selectByName(user.getUsername());
        if (user1 == null) {
            map.put("message","当前用户名不存在!");
            return map;
        }
        if (!user.getPassword().equals(user1.getPassword())) {
            map.put("message","当前用户名密码错误!");
            return map;
        }
        user.setUserId(user1.getUserId());

        HttpSession session = request.getSession(true);
        if (session != null) {
            session.setAttribute("user",user);
        }
        return map;
    }
}

9.2 实现前端代码

这里前端去除了前后空格,以及为空的情况

let submit = document.querySelector('.button');
        submit.onclick = function() {
            let username = document.querySelector('.user');
            let password = document.querySelector('.password');
            
            if (username.value.trim() == ""){
                alert('请先输入用户名!');
                username.focus();
                return;
            }
            if (password.value.trim() == ""){
                alert('请先输入密码!');
                password.focus();
                return;
            }
            $.ajax({
                url: "login",
                method: "POST",
                data: JSON.stringify({username: username.value.trim(), password: password.value.trim()}),
                contentType: "application/json;charset=utf-8",
                success: function(data, status) {
                    if(data.message == null) {
                        location.assign("home.html");
                    }else{
                        alert(data.message);
                        username.value="";
                        password.value="";
                        username.focus();
                    }
                }
            })
        }

10. 实现登录判断 — 拦截器

10.1 实现自定义拦截器

public class LoginInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        HttpSession session = request.getSession(false);
        if (session != null && session.getAttribute("user") != null) {
            return true;
        }
        response.setStatus(401);
        response.sendRedirect("/login.html");
        return false;
    }
}

10.2 将自定义拦截器加入到系统配置

@Configuration
public class AppConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new LoginInterceptor())
                .addPathPatterns("/**")
                .excludePathPatterns("/**/*.js")
                .excludePathPatterns("/**/*.jpg")
                .excludePathPatterns("/**/*.css")
                .excludePathPatterns("/**/*.png")
                .excludePathPatterns("/**/login.html")
                .excludePathPatterns("/**/register.html")
                .excludePathPatterns("/**/login")
                .excludePathPatterns("/**/register");
    }
}

11. 实现注册功能

这里的交互是 交互9

11.1 实现后端代码

实现一个类 Register 来接收前端返回来的数据

class Register {
    public String username;
    public String password1;
    public String password2;
}

这里后端需要判断当前用户名是否已经被使用.

@RestController
public class RegisterController {
    @Autowired
    private UserService userService;

    @RequestMapping("/register")
    public Object userRegister(@RequestBody Register register) {
        HashMap<String,Object> map = new HashMap<>();
        User user = userService.selectByName(register.username);
        if (user != null) {
            map.put("message","当前用户名已经存在了, 请更换!");
            return map;
        }

        User user1 = new User();
        user1.setUsername(register.username);
        user1.setPassword(register.password1);
        userService.addUser(user1);
        return map;
    }
}

11.2 实现前端代码

要对输入内容去除前后空格,并且判空

let submit = document.querySelector('.button');
        submit.onclick = function() {
            let username = document.querySelector('.user');
            let password1 = document.querySelector('.password1');
            let password2 = document.querySelector('.password2');
            if(username.value.trim() == ""){
                alert("请先输入用户名!");
                username.focus();
                return;
            }
            if(password1.value.trim() == ""){
                alert('请先输入密码!');
                password1.focus();
                return;
            }
            if(password2.value.trim() == ""){
                alert('请再次输入密码!');
                password2.focus();
                return;
            }
            if(password1.value.trim() != password2.value.trim()) {
                alert('两次输入的密码不同!');
                passwrod1.value="";
                password2.value="";
                return;
            }
            $.ajax({
                url: "register",
                method: "POST",
                data: JSON.stringify({username: username.value.trim(), password1: password1.value.trim(),password2: password2.value.trim()}),
                contentType: "application/json;charset=utf-8",
                success: function(data,status){
                    if(data.message != null){
                        alert(data.message);
                        username.value="";
                        password1.value="";
                        password2.value="";
                        username.focus();
                    }else{
                        location.assign('login.html');
                    }
                }
            })
        }

12. 实现注销功能

这里的交互是 交互10

12.1 实现后端代码

因为注销功能是点击注销的时候, 触发一个logout的url, 然后发送一个请求.
这里只需要实现后端代码既可

@Controller
public class LogoutController {

    @RequestMapping("/logout")
    public void userLogout(HttpServletRequest request, HttpServletResponse response) throws IOException {
        HttpSession session = request.getSession(false);
        // 拦截器的拦截, 所以不可能出现session为空的情况
        session.removeAttribute("user");
        response.sendRedirect("login.html");
    }
}

13. 实现博客编辑页

这里的交互是 交互1

13.1 实现后端代码

@RestController
public class EditController {
    @Autowired
    private BlogService blogService;

    @RequestMapping("/edit")
    public void postBlog(@RequestBody Blog blog, @SessionAttribute(value = "user",required = false)User user){
        blog.setPostTime(new Timestamp(System.currentTimeMillis()));
        blog.setUserId(user.getUserId());

        blogService.postBlog(blog);
    }
}

13.2 实现前端代码

let submit = document.querySelector('.publish');
        submit.onclick = function() {
            let title = document.querySelector('.title');
            let content = document.querySelector('.content');
            if(title.value.trim() == ""){
                alert('当前文章标题为空,请输入!');
                title.focus();
                return;
            }
            if(content.value.trim() == ""){
                alert('当前文章内容为空,请输入!');
                content.focus();
                return;
            }
            $.ajax({
                url: "edit",
                method: "POST",
                data: JSON.stringify({title: title.value.trim(), content: content.value.trim()}),
                contentType: "application/json;charset=utf-8",
                success: function(data,status) {
                    location.assign('home.html');
                }
            })
        }

14. 实现博客个人主页

这里的交互是 交互7
这里的前端页面主要就是主页页面的改进

14.1 实现后端代码

@RestController
public class PersonController {
    @Autowired
    private BlogService blogService;

    @RequestMapping("/person")
    public List<Blog> getMyBlog(@SessionAttribute(value = "user",required = false)User user) {
        List<Blog> blogs = blogService.getAllBlogById(user.getUserId());
        for (Blog blog : blogs) {
            if (blog.getContent().length() > 80) {
                blog.setContent(blog.getContent().substring(0,80) + " ...");
            }
        }
        return blogs;
    }
}

14.2 实现前端代码

$.ajax({
            url: "person",
            method: "GET",
            success: function(data,status) {
                buildBlogs(data);
            }
        })

        function buildBlogs(blogs){
            let rightDiv = document.querySelector('.right');
            for(let blog of blogs){
                let blogDiv = document.createElement('div');
                blogDiv.className = 'article';
                // 创建 title
                let h2 = document.createElement('h2');
                h2.className = 'title';
                h2.innerHTML = blog.title;
                blogDiv.appendChild(h2);
                // 创建 postTime
                let postTime = document.createElement('span');
                postTime.className = 'date';
                postTime.innerHTML = DateFormat(blog.postTime);
                blogDiv.appendChild(postTime);
                // 创建 content
                let content = document.createElement('div');
                content.className = 'desc';
                content.innerHTML = blog.content;
                blogDiv.appendChild(content);
                // 创建 详情页的超链接
                let detailA = document.createElement('a');
                detailA.className = 'more';
                detailA.href = 'art.html?blogId=' + blog.blogId;
                detailA.innerHTML = '查看全文&gt;&gt;';
                blogDiv.appendChild(detailA);
                // 加入到 right 中
                rightDiv.appendChild(blogDiv);
            }
        }

        // 把毫秒级时间戳转化成格式化日期
        function DateFormat(timeStampMS) {
            var date = new Date(timeStampMS);
 
            var year = date.getFullYear(),
                month = date.getMonth()+1,//月份是从0开始的
                day = date.getDate(),
                hour = date.getHours(),
                min = date.getMinutes(),
                sec = date.getSeconds();
            var newTime = year + '-' +
                        (month < 10? '0' + month : month) + '-' +
                        (day < 10? '0' + day : day) + ' ' +
                        (hour < 10? '0' + hour : hour) + ':' +
                        (min < 10? '0' + min : min) + ':' +
                        (sec < 10? '0' + sec : sec);
        
            return newTime;
        }

15. 实现展示用户信息的功能

这里的交互是 交互11

这里需要分情况考虑, 展示个人信息主要是主页页面, 详情页面, 个人主页页面.
以带不带blogId来区分

15.1 实现后端代码

这里判断了 blogId丢失的情况以及,文章作者丢失情况(数据库表数据被删除的时候会出现这种错误)

@RestController
public class UserController {
    @Autowired
    private UserService userService;
    @Autowired
    private BlogService blogService;

    @RequestMapping("/user")
    public Object getUser(Integer blogId, @SessionAttribute(value = "user",required = false)User user){
        if(blogId == null) {
            return user;
        }else {
            HashMap<String,Object> map = new HashMap<>();
            Blog blog = blogService.getBlogByBid(blogId);
            if(blog == null) {
                map.put("message","不存在当前blogId的文章");
                return map;
            }
            User author = userService.selectById(blog.getUserId());
            if(author == null){
                map.put("message","当前文章作者出错");
                return map;
            }
            return author;
        }
    }
}

15.2 实现前端代码

详情页的情况:

$.ajax({
            url: "user"+location.search,
            method: "GET",
            success: function(data,status) {
                if(data.message == null){
                    let username = document.querySelector('.name');
                    username.innerHTML = data.username;
                }else{
                    alert(data.message);
                    location.assign('home.html');
                }
            }
        })

个人主页和主页的情况

$.ajax({
            url: "user",
            method: "GET",
            success: function(data,status){
                let username = document.querySelector('.name');
                username.innerHTML = data.username;
            }
        })

16. 实现博客的删除功能

这里需要用到 交互2
这里在详情页的时候进行构建, 在Blog实体类中加一项 isAuthor, 为1的时候就是当前文章就是作者.
前端接收到这个的时候, 进行判断, 如果为1就显示删除的按钮.

16.1 改进代码

16.2 实现后端代码

@Controller
public class DeleteController {
    @Autowired
    private BlogService blogService;

    @RequestMapping("/delete")
    public Object deleteBlog(Integer blogId) {
        blogService.deleteBlog(blogId);
        return "/home.html";
    }
}

17. 实现博客的修改功能

这里的交互是 交互3 和 交互4
交互3是在新的页面进行加载

17.1 实现后端代码

@RestController
public class UpdateController {
    @Autowired
    private BlogService blogService;

    @RequestMapping("/updateLoad")
    public Object updateLoad(Integer blogId){
        HashMap<String, Object> map = new HashMap<>();
        if(blogId == null) {
            map.put("message","blogId丢失!");
            return map;
        }
        Blog blog = blogService.getBlogByBid(blogId);
        if(blog == null) {
            map.put("blog","不存在当前blog的文章!");
            return map;
        }
        return blog;
    }

    @RequestMapping("/update")
    public Object Update(Integer blogId, @RequestBody Blog blog, @SessionAttribute(value = "user",required = false)User user) {
        HashMap<String, Object> map = new HashMap<>();
        if(blogId == null) {
            map.put("message","blogId丢失!");
            return map;
        }
        blog.setBlogId(blogId);
        blog.setUserId(user.getUserId());
        blogService.updateBlog(blog);
        return map;
    }
}

17.2 实现前端代码

$.ajax({
            url: "updateLoad"+location.search,
            method: "GET",
            success: function(data,status) {
                if(data.message == null) {
                    let title = document.querySelector('.title');
                    title.value=data.title;
                    let content = document.querySelector('.content');
                    content.value=data.content;
                }else{
                    alert(data.message);
                    location.assign('home.html');
                }
            }
        })

        // 初始化编辑器
        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%",
            // 高度 100% 意思是和父元素一样高. 要在父元素的基础上去掉标题编辑区的高度
            height: "calc(100% - 60px)",

            // 指定 editor.md 依赖的插件路径
            path: "editor.md/lib/",
            // 放到 textarea中
            saveHTMLToTextArea: true
        });

        let submit = document.querySelector('.publish');
        submit.onclick = function() {
            let title = document.querySelector('.title');
            let content = document.querySelector('.content');
            if(title.value.trim() == ""){
                alert('当前文章标题为空,请输入!');
                title.focus();
                return;
            }
            if(content.value.trim() == ""){
                alert('当前文章内容为空,请输入!');
                content.focus();
                return;
            }
            $.ajax({
                url: "update"+location.search,
                method: "POST",
                data: JSON.stringify({title: title.value.trim(), content: content.value.trim()}),
                contentType: "application/json;charset=utf-8",
                success: function(data,status) {
                    if(data.message == null){
                        location.assign('home.html');
                    }else{
                        alert(data.message);
                        location.assign('home.html');
                    }
                }
            })
        }

基于 SpringBoot + MyBatis 的博客系统