SpringBoot学习笔记-创建个人中心页面（上）

笔记内容转载自 AcWing 的 SpringBoot 框架课讲义，课程链接：AcWing SpringBoot 框架课。

1. 更新数据库表
2. 实现后端API

1. 更新数据库表

我们需要创建一个表来保存 Bot 的信息，新建一个 bot 表，包含以下几个列：

id: int：非空、自动增加、唯一、主键。
user_id: int：非空。注意：在 pojo 中需要定义成 userId，在 queryWrapper 中的名称仍然为 user_id。
title: varchar(100)。
description: varchar(300)。
content：varchar(10000)。
rating: int：默认值为1500。
createtime: datetime，注意：在 pojo 中定义日期格式的注解：@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")。
modifytime: datetime。

可以使用如下 SQL 语句一键创建好该表：

CREATE TABLE `kob`.`bot` (
    `id` int NOT NULL AUTO_INCREMENT,
    `user_id` int NOT NULL,
    `title` varchar(100) NULL,
    `description` varchar(300) NULL,
    `content` varchar(10000) NULL,
    `rating` int NULL DEFAULT 1500,
    `createtime` datetime NULL,
    `modifytime` datetime NULL,
    PRIMARY KEY (`id`)
);

创建好数据库表后我们需要创建一个 pojo，在 pojo 目录下创建 Bot 类：

java">package com.kob.backend.pojo;

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableId;
import com.fasterxml.jackson.annotation.JsonFormat;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

import java.util.Date;

@Data
@NoArgsConstructor
@AllArgsConstructor
public class Bot {
    @TableId(value = "id", type = IdType.AUTO)  // 声明id为自增类型
    private Integer id;
    private Integer userID;  // 注意驼峰命名
    private String title;
    private String description;
    private String content;
    private Integer rating;
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")  // 注意日期格式的设置
    private Date createtime;
    @JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss")
    private Date modifytime;
}

然后就可以实现 mapper，在 mapper 目录下创建 BotMapper 接口：

java">package com.kob.backend.mapper;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.kob.backend.pojo.Bot;
import org.apache.ibatis.annotations.Mapper;

@Mapper
public interface BotMapper extends BaseMapper<Bot> {
}

2. 实现后端API

首先在 service.user 包下创建 bot 包存放与 Bot 相关的 Service 代码，然后在 service.impl.user 包下创建 bot 包存放相应的 Service 实现代码，最后在 controller.user 包下创建 bot 包存放 Controller。

我们需要实现以下四个 API：

/user/bot/add/：创建一个 Bot。
/user/bot/remove/：删除一个 Bot。
/user/bot/update/：修改一个 Bot。
/user/bot/getlist/：查询 Bot 列表。

在 service.user.bot 包下创建这四个 API 的 Service 接口：

（1）AddService：

java">package com.kob.backend.service.user.bot;

import java.util.Map;

public interface AddService {
    Map<String, String> add(Map<String, String> data);
}

（2）RemoveService：

java">package com.kob.backend.service.user.bot;

import java.util.Map;

public interface RemoveService {
    Map<String, String> remove(Map<String, String> data);
}

（3）UpdateService：

java">package com.kob.backend.service.user.bot;

import java.util.Map;

public interface UpdateService {
    Map<String, String> update(Map<String, String> data);
}

（4）GetListService：

java">package com.kob.backend.service.user.bot;

import com.kob.backend.pojo.Bot;

import java.util.List;

public interface GetListService {
    List<Bot> getList();  // 根据用户信息获取Bot，用户信息存放在令牌中，因此不用传参数
}

接下来在 service.impl.user.bot 包下创建这四个 Service 接口的实现：

（1）AddServiceImpl：

java">package com.kob.backend.service.impl.user.bot;

import com.kob.backend.mapper.BotMapper;
import com.kob.backend.pojo.Bot;
import com.kob.backend.pojo.User;
import com.kob.backend.service.impl.utils.UserDetailsImpl;
import com.kob.backend.service.user.bot.AddService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;

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

@Service
public class AddServiceImpl implements AddService {
    @Autowired
    private BotMapper botMapper;

    @Override
    public Map<String, String> add(Map<String, String> data) {
        UsernamePasswordAuthenticationToken authenticationToken =
                (UsernamePasswordAuthenticationToken) SecurityContextHolder.getContext().getAuthentication();
        UserDetailsImpl loginUser = (UserDetailsImpl) authenticationToken.getPrincipal();
        User user = loginUser.getUser();  // 获取当前登录的用户

        String title = data.get("title");
        String description = data.get("description");
        String content = data.get("content");

        Map<String, String> res = new HashMap<>();

        if (title == null || title.isEmpty()) {
            res.put("result", "The title can't be empty!");
            return res;
        }
        if (title.length() > 100) {
            res.put("result", "Title length can't exceed 100!");
            return res;
        }
        if (description == null || description.isEmpty()) {
            description = "这个用户很懒，什么也没留下~";
        }
        if (description.length() > 300) {
            res.put("result", "Description length can't exceed 300!");
            return res;
        }
        if (content == null || content.isEmpty()) {
            res.put("result", "The content can't be empty!");
            return res;
        }
        if (content.length() > 10000) {
            res.put("result", "Code length can't exceed 10000!");
            return res;
        }

        Date now = new Date();
        Bot bot = new Bot(null, user.getId(), title, description, content, 1500, now, now);
        botMapper.insert(bot);

        res.put("result", "success");
        return res;
    }
}

（2）RemoveServiceImpl：

java">package com.kob.backend.service.impl.user.bot;

import com.kob.backend.mapper.BotMapper;
import com.kob.backend.pojo.Bot;
import com.kob.backend.pojo.User;
import com.kob.backend.service.impl.utils.UserDetailsImpl;
import com.kob.backend.service.user.bot.RemoveService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;

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

@Service
public class RemoveServiceImpl implements RemoveService {
    @Autowired
    private BotMapper botMapper;

    @Override
    public Map<String, String> remove(Map<String, String> data) {
        UsernamePasswordAuthenticationToken authenticationToken =
                (UsernamePasswordAuthenticationToken) SecurityContextHolder.getContext().getAuthentication();
        UserDetailsImpl loginUser = (UserDetailsImpl) authenticationToken.getPrincipal();
        User user = loginUser.getUser();  // 需要判断要删除的Bot是不是当前登录用户的Bot

        int bot_id = Integer.parseInt(data.get("bot_id"));
        Bot bot = botMapper.selectById(bot_id);

        Map<String, String> res = new HashMap<>();

        if (bot == null) {
            res.put("result", "Bot doesn't exist!");
            return res;
        }
        if (!bot.getUserID().equals(user.getId())) {
            res.put("result", "No permission to delete the bot!");
            return res;
        }

        botMapper.deleteById(bot_id);

        res.put("result", "success");
        return null;
    }
}

（3）UpdateServiceImpl：

java">package com.kob.backend.service.impl.user.bot;

import com.kob.backend.mapper.BotMapper;
import com.kob.backend.pojo.Bot;
import com.kob.backend.pojo.User;
import com.kob.backend.service.impl.utils.UserDetailsImpl;
import com.kob.backend.service.user.bot.UpdateService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;

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

@Service
public class UpdateServiceImpl implements UpdateService {
    @Autowired
    private BotMapper botMapper;

    @Override
    public Map<String, String> update(Map<String, String> data) {
        UsernamePasswordAuthenticationToken authenticationToken =
                (UsernamePasswordAuthenticationToken) SecurityContextHolder.getContext().getAuthentication();
        UserDetailsImpl loginUser = (UserDetailsImpl) authenticationToken.getPrincipal();
        User user = loginUser.getUser();

        int bot_id = Integer.parseInt(data.get("bot_id"));
        String title = data.get("title");
        String description = data.get("description");
        String content = data.get("content");

        Map<String, String> res = new HashMap<>();

        if (title == null || title.isEmpty()) {
            res.put("result", "The title can't be empty!");
            return res;
        }
        if (title.length() > 100) {
            res.put("result", "Title length can't exceed 100!");
            return res;
        }
        if (description == null || description.isEmpty()) {
            description = "这个用户很懒，什么也没留下~";
        }
        if (description.length() > 300) {
            res.put("result", "Description length can't exceed 300!");
            return res;
        }
        if (content == null || content.isEmpty()) {
            res.put("result", "The content can't be empty!");
            return res;
        }
        if (content.length() > 10000) {
            res.put("result", "Code length can't exceed 10000!");
            return res;
        }

        Bot bot = botMapper.selectById(bot_id);

        if (bot == null) {
            res.put("result", "Bot doesn't exist!");
            return res;
        }
        if (!bot.getUserID().equals(user.getId())) {
            res.put("result", "No permission to update the bot!");
            return res;
        }

        Bot new_bot = new Bot(bot.getId(), user.getId(), title, description, content, bot.getRating(), bot.getCreatetime(), new Date());
        botMapper.updateById(new_bot);

        res.put("result", "success");
        return null;
    }
}

（4）GetListServiceImpl：

java">package com.kob.backend.service.impl.user.bot;

import com.baomidou.mybatisplus.core.conditions.query.QueryWrapper;
import com.kob.backend.mapper.BotMapper;
import com.kob.backend.pojo.Bot;
import com.kob.backend.pojo.User;
import com.kob.backend.service.impl.utils.UserDetailsImpl;
import com.kob.backend.service.user.bot.GetListService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class GetListServiceImpl implements GetListService {
    @Autowired
    private BotMapper botMapper;

    @Override
    public List<Bot> getList() {
        UsernamePasswordAuthenticationToken authenticationToken =
                (UsernamePasswordAuthenticationToken) SecurityContextHolder.getContext().getAuthentication();
        UserDetailsImpl loginUser = (UserDetailsImpl) authenticationToken.getPrincipal();
        User user = loginUser.getUser();

        QueryWrapper<Bot> queryWrapper = new QueryWrapper<>();
        queryWrapper.eq("user_id", user.getId());

        return botMapper.selectList(queryWrapper);
    }
}

最后在 controller.user.bot 包下创建对应的 Controller：

（1）AddController：

java">package com.kob.backend.controller.user.bot;

import com.kob.backend.service.user.bot.AddService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Map;

@RestController
public class AddController {
    @Autowired
    private AddService addService;

    @PostMapping("/user/bot/add/")
    public Map<String, String> add(@RequestParam Map<String, String> data) {
        return addService.add(data);
    }
}

（2）RemoveController：

java">package com.kob.backend.controller.user.bot;

import com.kob.backend.service.user.bot.RemoveService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Map;

@RestController
public class RemoveController {
    @Autowired
    private RemoveService removeService;

    @PostMapping("/user/bot/remove/")
    public Map<String, String> remove(@RequestParam Map<String, String> data) {
        return removeService.remove(data);
    }
}

（3）UpdateController：

java">package com.kob.backend.controller.user.bot;

import com.kob.backend.service.user.bot.UpdateService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.util.Map;

@RestController
public class UpdateController {
    @Autowired
    private UpdateService updateService;

    @PostMapping("/user/bot/update/")
    public Map<String, String> update(@RequestParam Map<String, String> data) {
        return updateService.update(data);
    }
}

（4）GetListController：

java">package com.kob.backend.controller.user.bot;

import com.kob.backend.pojo.Bot;
import com.kob.backend.service.user.bot.GetListService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.List;

@RestController
public class GetListController {
    @Autowired
    private GetListService getListService;

    @GetMapping("/user/bot/getlist/")
    public List<Bot> getList() {
        return getListService.getList();
    }
}