mall是一个开源的电商项目,感觉不错,拿来学习,跟着教学文档学习,自己也一点点来整理学习内容加深印象
mall教学地址mall-learing

整合Springboot和Mybatis搭建项目基础骨架

mysql数据库环境搭建

数据库脚本地址

项目使用框架

1.SpringBoot

快速构建项目的基础

2.Mybatis

数据库ORM框架

3.PagerHelps

Mybatis的分页插件

4.Druid

alibaba的开源数据库连接池

5.Mybatis generator

mybatis代码生成器插件

项目源码地址

https://github.com/macrozheng/mall-learning/tree/master/mall-tiny-01

搭建项目环境

1.使用IDEA初始化一个SpringBoot项目
2.添加项目依赖修改pom.xml文件

<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <dependencies>
        <!--SpringBoot通用依赖模块-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--MyBatis分页插件-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>1.2.10</version>
        </dependency>
        <!--集成druid连接池-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
        <!-- MyBatis 生成器 -->
        <dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-core</artifactId>
            <version>1.3.3</version>
        </dependency>
        <!--Mysql数据库驱动-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.15</version>
        </dependency>
    </dependencies>

3.修改application.yml文件(默认项目生成的是application.properties文件,修改下.)

server:
  port: 8080

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/mall?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai
    username: root
    password: root

mybatis:
  mapper-locations:
    - classpath:mapper/*.xml
    - classpath*:com/**/mapper/*.xml

4.项目结构

官网的项目结构图

5.配置自动生成mybatis所需model、mapper.xml、mapper接口和Example的配置文件generatorConfig.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
    <properties resource="generator.properties"/>
    <context id="MySqlContext" targetRuntime="MyBatis3" defaultModelType="flat">
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>
        <property name="javaFileEncoding" value="UTF-8"/>
        <!-- 为模型生成序列化方法-->
        <plugin type="org.mybatis.generator.plugins.SerializablePlugin"/>
        <!-- 为生成的Java模型创建一个toString方法 -->
        <plugin type="org.mybatis.generator.plugins.ToStringPlugin"/>
        <!--可以自定义生成model的代码注释-->
        <commentGenerator type="com.macro.mall.tiny.mbg.CommentGenerator">
            <!-- 是否去除自动生成的注释 true：是 ： false:否 -->
            <property name="suppressAllComments" value="true"/>
            <property name="suppressDate" value="true"/>
            <property name="addRemarkComments" value="true"/>
        </commentGenerator>
        <!--配置数据库连接-->
        <jdbcConnection driverClass="${jdbc.driverClass}"
                        connectionURL="${jdbc.connectionURL}"
                        userId="${jdbc.userId}"
                        password="${jdbc.password}">
            <!--解决mysql驱动升级到8.0后不生成指定数据库代码的问题-->
            <property name="nullCatalogMeansCurrent" value="true" />
        </jdbcConnection>
        <!--指定生成model的路径-->
        <javaModelGenerator targetPackage="com.macro.mall.tiny.mbg.model" targetProject="mall-tiny-01\src\main\java"/>
        <!--指定生成mapper.xml的路径-->
        <sqlMapGenerator targetPackage="com.macro.mall.tiny.mbg.mapper" targetProject="mall-tiny-01\src\main\resources"/>
        <!--指定生成mapper接口的的路径-->
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.macro.mall.tiny.mbg.mapper"
                             targetProject="mall-tiny-01\src\main\java"/>
        <!--生成全部表tableName设为%-->
        <table tableName="pms_brand">
            <generatedKey column="id" sqlStatement="MySql" identity="true"/>
        </table>
    </context>
</generatorConfiguration>

6.配置代码生成器的数据库连接配置

jdbc.driverClass=com.mysql.cj.jdbc.Driver
jdbc.connectionURL=jdbc:mysql://localhost:3306/mall?useUnicode=true&characterEncoding=utf-8&serverTimezone=Asia/Shanghai&nullCatalogMeansCurrent=true
jdbc.userId=root
jdbc.password=root

7.创建生成代码的执行类

package com.macro.mall.tiny.mbg;

import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;

import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;

/**
 * 用于生产MBG的代码
 * Created by macro on 2018/4/26.
 */
public class Generator {
    public static void main(String[] args) throws Exception {
        //MBG 执行过程中的警告信息
        List<String> warnings = new ArrayList<String>();
        //当生成的代码重复时，覆盖原代码
        boolean overwrite = true;
        //读取我们的 MBG 配置文件
        InputStream is = Generator.class.getResourceAsStream("/generatorConfig.xml");
        ConfigurationParser cp = new ConfigurationParser(warnings);
        Configuration config = cp.parseConfiguration(is);
        is.close();

        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        //创建 MBG
        MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
        //执行生成代码
        myBatisGenerator.generate(null);
        //输出警告信息
        for (String warning : warnings) {
            System.out.println(warning);
        }
    }
}

8.添加Mybatis的java配置

用于配置需要动态生成的mapper接口的路径
@MapperScan为指向你存放mapper接口的路径

package com.macro.mall.tiny.config;

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.context.annotation.Configuration;

/**
 * MyBatis配置类
 * Created by macro on 2019/4/8.
 */
@Configuration
@MapperScan("com.macro.mall.tiny.mbg.mapper")
public class MyBatisConfig {
}

9.建立公共类
IErrorCode

package com.mall.mallmybatis.common.api;
/**
 * 封装API的错误码
 */
public interface IErrorCode {
    long getCode();
    String getMessage();
}

ResultCode

package com.mall.mallmybatis.common.api;
/**
 * 枚举了一些常用API操作码
 * @author wangxing
 * @version 2020/6/22 10:29 Administrator
 */
public enum ResultCode implements IErrorCode {
    SUCCESS(200, "操作成功"),
    FAILED(500, "操作失败"),
    VALIDATE_FAILED(404, "参数检验失败"),
    UNAUTHORIZED(401, "暂未登录或token已经过期"),
    FORBIDDEN(403, "没有相关权限");
    private long code;
    private String message;

    private ResultCode(long code, String message) {
        this.code = code;
        this.message = message;
    }

    public long getCode() {
        return code;
    }
    public String getMessage() {
        return message;
    }
}

CommonResult

package com.mall.mallmybatis.common.api;

/**
 * 通用返回对象
 */
public class CommonResult<T> {
    private long code;
    private String message;
    private T data;

    protected CommonResult() {
    }

    protected CommonResult(long code, String message, T data) {
        this.code = code;
        this.message = message;
        this.data = data;
    }

    /**
     * 成功返回结果
     *
     * @param data 获取的数据
     */
    public static <T> CommonResult<T> success(T data) {
        return new CommonResult<T>(ResultCode.SUCCESS.getCode(), ResultCode.SUCCESS.getMessage(), data);
    }

    /**
     * 成功返回结果
     *
     * @param data 获取的数据
     * @param  message 提示信息
     */
    public static <T> CommonResult<T> success(T data, String message) {
        return new CommonResult<T>(ResultCode.SUCCESS.getCode(), message, data);
    }

    /**
     * 失败返回结果
     * @param errorCode 错误码
     */
    public static <T> CommonResult<T> failed(IErrorCode errorCode) {
        return new CommonResult<T>(errorCode.getCode(), errorCode.getMessage(), null);
    }

    /**
     * 失败返回结果
     * @param message 提示信息
     */
    public static <T> CommonResult<T> failed(String message) {
        return new CommonResult<T>(ResultCode.FAILED.getCode(), message, null);
    }

    /**
     * 失败返回结果
     */
    public static <T> CommonResult<T> failed() {
        return failed(ResultCode.FAILED);
    }

    /**
     * 参数验证失败返回结果
     */
    public static <T> CommonResult<T> validateFailed() {
        return failed(ResultCode.VALIDATE_FAILED);
    }

    /**
     * 参数验证失败返回结果
     * @param message 提示信息
     */
    public static <T> CommonResult<T> validateFailed(String message) {
        return new CommonResult<T>(ResultCode.VALIDATE_FAILED.getCode(), message, null);
    }

    /**
     * 未登录返回结果
     */
    public static <T> CommonResult<T> unauthorized(T data) {
        return new CommonResult<T>(ResultCode.UNAUTHORIZED.getCode(), ResultCode.UNAUTHORIZED.getMessage(), data);
    }

    /**
     * 未授权返回结果
     */
    public static <T> CommonResult<T> forbidden(T data) {
        return new CommonResult<T>(ResultCode.FORBIDDEN.getCode(), ResultCode.FORBIDDEN.getMessage(), data);
    }

    public long getCode() {
        return code;
    }

    public void setCode(long code) {
        this.code = code;
    }

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }

    public T getData() {
        return data;
    }

    public void setData(T data) {
        this.data = data;
    }
}

CommonPage

package com.mall.mallmybatis.common.api;
import com.github.pagehelper.PageInfo;
import java.util.List;

/**
 * 分页数据封装类
 * @author wangxing
 * @version 2020/6/22 10:34 Administrator
 */
public class CommonPage<T> {
    private Integer pageNum;
    private Integer pageSize;
    private Integer totalPage;
    private Long total;
    private List<T> list;

    /**
     * 将PageHelper分页后的list转为分页信息
     */
    public static <T> CommonPage<T> restPage(List<T> list) {
        CommonPage<T> result = new CommonPage<T>();
        PageInfo<T> pageInfo = new PageInfo<T>(list);
        result.setTotalPage(pageInfo.getPages());
        result.setPageNum(pageInfo.getPageNum());
        result.setPageSize(pageInfo.getPageSize());
        result.setTotal(pageInfo.getTotal());
        result.setList(pageInfo.getList());
        return result;
    }

    public Integer getPageNum() {
        return pageNum;
    }

    public void setPageNum(Integer pageNum) {
        this.pageNum = pageNum;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

    public Integer getTotalPage() {
        return totalPage;
    }

    public void setTotalPage(Integer totalPage) {
        this.totalPage = totalPage;
    }

    public List<T> getList() {
        return list;
    }

    public void setList(List<T> list) {
        this.list = list;
    }

    public Long getTotal() {
        return total;
    }

    public void setTotal(Long total) {
        this.total = total;
    }
}

添加Service接口

package com.macro.mall.tiny.service;


import com.macro.mall.tiny.mbg.model.PmsBrand;

import java.util.List;

/**
 * PmsBrandService
 * Created by macro on 2019/4/19.
 */
public interface PmsBrandService {
    List<PmsBrand> listAllBrand();

    int createBrand(PmsBrand brand);

    int updateBrand(Long id, PmsBrand brand);

    int deleteBrand(Long id);

    List<PmsBrand> listBrand(int pageNum, int pageSize);

    PmsBrand getBrand(Long id);
}

实现Service接口

package com.macro.mall.tiny.service.impl;

import com.github.pagehelper.PageHelper;
import com.macro.mall.tiny.mbg.mapper.PmsBrandMapper;
import com.macro.mall.tiny.mbg.model.PmsBrand;
import com.macro.mall.tiny.mbg.model.PmsBrandExample;
import com.macro.mall.tiny.service.PmsBrandService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

/**
 * PmsBrandService实现类
 * Created by macro on 2019/4/19.
 */
@Service
public class PmsBrandServiceImpl implements PmsBrandService {
    @Autowired
    private PmsBrandMapper brandMapper;

    @Override
    public List<PmsBrand> listAllBrand() {
        return brandMapper.selectByExample(new PmsBrandExample());
    }

    @Override
    public int createBrand(PmsBrand brand) {
        return brandMapper.insertSelective(brand);
    }

    @Override
    public int updateBrand(Long id, PmsBrand brand) {
        brand.setId(id);
        return brandMapper.updateByPrimaryKeySelective(brand);
    }

    @Override
    public int deleteBrand(Long id) {
        return brandMapper.deleteByPrimaryKey(id);
    }

    @Override
    public List<PmsBrand> listBrand(int pageNum, int pageSize) {
        PageHelper.startPage(pageNum, pageSize);
        return brandMapper.selectByExample(new PmsBrandExample());
    }

    @Override
    public PmsBrand getBrand(Long id) {
        return brandMapper.selectByPrimaryKey(id);
    }
}

实现Controller中的接口

package com.macro.mall.tiny.controller;

import com.macro.mall.tiny.common.api.CommonPage;
import com.macro.mall.tiny.common.api.CommonResult;
import com.macro.mall.tiny.mbg.model.PmsBrand;
import com.macro.mall.tiny.service.PmsBrandService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.annotation.*;

import java.util.List;


/**
 * 品牌管理Controller
 * Created by macro on 2019/4/19.
 */
@Controller
@RequestMapping("/brand")
public class PmsBrandController {
    @Autowired
    private PmsBrandService demoService;

    private static final Logger LOGGER = LoggerFactory.getLogger(PmsBrandController.class);

    @RequestMapping(value = "listAll", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult<List<PmsBrand>> getBrandList() {
        return CommonResult.success(demoService.listAllBrand());
    }

    @RequestMapping(value = "/create", method = RequestMethod.POST)
    @ResponseBody
    public CommonResult createBrand(@RequestBody PmsBrand pmsBrand) {
        CommonResult commonResult;
        int count = demoService.createBrand(pmsBrand);
        if (count == 1) {
            commonResult = CommonResult.success(pmsBrand);
            LOGGER.debug("createBrand success:{}", pmsBrand);
        } else {
            commonResult = CommonResult.failed("操作失败");
            LOGGER.debug("createBrand failed:{}", pmsBrand);
        }
        return commonResult;
    }

    @RequestMapping(value = "/update/{id}", method = RequestMethod.POST)
    @ResponseBody
    public CommonResult updateBrand(@PathVariable("id") Long id, @RequestBody PmsBrand pmsBrandDto, BindingResult result) {
        CommonResult commonResult;
        int count = demoService.updateBrand(id, pmsBrandDto);
        if (count == 1) {
            commonResult = CommonResult.success(pmsBrandDto);
            LOGGER.debug("updateBrand success:{}", pmsBrandDto);
        } else {
            commonResult = CommonResult.failed("操作失败");
            LOGGER.debug("updateBrand failed:{}", pmsBrandDto);
        }
        return commonResult;
    }

    @RequestMapping(value = "/delete/{id}", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult deleteBrand(@PathVariable("id") Long id) {
        int count = demoService.deleteBrand(id);
        if (count == 1) {
            LOGGER.debug("deleteBrand success :id={}", id);
            return CommonResult.success(null);
        } else {
            LOGGER.debug("deleteBrand failed :id={}", id);
            return CommonResult.failed("操作失败");
        }
    }

    @RequestMapping(value = "/list", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult<CommonPage<PmsBrand>> listBrand(@RequestParam(value = "pageNum", defaultValue = "1") Integer pageNum,
                                                        @RequestParam(value = "pageSize", defaultValue = "3") Integer pageSize) {
        List<PmsBrand> brandList = demoService.listBrand(pageNum, pageSize);
        return CommonResult.success(CommonPage.restPage(brandList));
    }

    @RequestMapping(value = "/{id}", method = RequestMethod.GET)
    @ResponseBody
    public CommonResult<PmsBrand> brand(@PathVariable("id") Long id) {
        return CommonResult.success(demoService.getBrand(id));
    }
}

搭建过程中的小问题

1.代码生成器生成的mapper.xml文件内容重复
错误提示

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'pmsBrandController': 
Unsatisfied dependency expressed through field 'pmsBrandService'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'pmsBrandServiceImpl': 
Unsatisfied dependency expressed through field 'pmsBrandMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: 
Error creating bean with name 'pmsBrandMapper' defined in file [E:\IdeaProjects\SpringBootLearn\mallmybatis\target\classes\com\mall\mallmybatis\mbg\mapper\PmsBrandMapper.class]: 
Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [org/mybatis/spring/boot/autoconfigure/MybatisAutoConfiguration.class]: 
Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]:
 Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 
'file [E:\IdeaProjects\SpringBootLearn\mallmybatis\target\classes\com\mall\mallmybatis\mbg\mapper\PmsBrandMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [E:\IdeaProjects\SpringBootLearn\mallmybatis\target\classes\com\mall\mallmybatis\mbg\mapper\PmsBrandMapper.xml]'. Cause: java.lang.IllegalArgumentException: Result Maps collection already contains value for com.mall.mallmybatis.mbg.mapper.PmsBrandMapper.BaseResultMap

产生问题原因

使用mybatis generator 生成mapper.xml时在mapper.xml中产生了重复的代码,原因是在mysql中有多个用户导致的

处理方案

在配置时调整数据库连接参数添加nullCatalogMeansCurrent=true
参考链接
https://www.jianshu.com/p/dbeeac29ff27