Springboot轻松整合Mybatis

缺乏、安全感 2021-12-10 13:09 165阅读 0赞

在springboot没有出现之前，spring整合mybatis是相当麻烦，各种bean配置，现在我们来感受一下Springboot整合Mybatis是有多么方便

# 先来看看效果 #

添加用户：  
![add][]  
查询用户：

![find][]

# 开始动手 #

## 第一步创建springboot项目 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTQ0OTI2NjU_size_16_color_FFFFFF_t_70]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTQ0OTI2NjU_size_16_color_FFFFFF_t_70 1]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTQ0OTI2NjU_size_16_color_FFFFFF_t_70 2]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTQ0OTI2NjU_size_16_color_FFFFFF_t_70 3]  
到这里项目就创建完成了，我们可以看看pom文件：

<dependencies>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-web</artifactId>
            </dependency>
            <dependency>
                <groupId>org.mybatis.spring.boot</groupId>
                <artifactId>mybatis-spring-boot-starter</artifactId>
                <version>2.0.1</version>
            </dependency>
    
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <scope>runtime</scope>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <version>1.16.10</version>
            </dependency>
    
        </dependencies>

## 动手创建类 ##

首先看看我的目录结构：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTQ0OTI2NjU_size_16_color_FFFFFF_t_70 4]

### 创建model user ###

package com.hawk.yoga.model;
    
    import lombok.Data;
    
    /**
     * @Author: 
     * @Description: user
     * @Date: Create in  2019/7/13
     */
    @Data
    public class User {
        private Integer age;
    
        private String name;
    
    //实际项目中不用Double，用更精确的
        private Double money;
    }

### 创建统一返回结果 ###

package com.hawk.yoga.common.result;
    
    import com.hawk.yoga.common.CodeEnum;
    import lombok.Data;
    
    /**
     * @Author: 
     * @Description: 自定义返回结果
     * @Date: Create in  2019/7/13
     */
    @Data
    public class YogaResult<T> {
    
        private String code;
    
        private T data;
    
        private YogaResult(){
            code = CodeEnum.OK.getCode().toString();
        }
    
        public static YogaResult ok(){
            return new YogaResult();
        }
    
        public static <T>YogaResult ok(T data){
            YogaResult yogaResult = new YogaResult();
            yogaResult.setData(data);
            return yogaResult;
        }
    }

### 创建code表 ###

package com.hawk.yoga.common;
    
    import lombok.Data;
    import lombok.Getter;
    
    /**
     * @Author: 
     * @Description:
     * @Date: Create in  2019/7/13
     */
    public enum CodeEnum {
        /**
         * 2开通频段为成功
         */
        OK("ok",2000),
        /**
         * 4开头频段为错误
         */
        ERROR("error",4000);
    
        CodeEnum(String desc,Integer code){
            this.code = code;
            this.desc = desc;
        }
        @Getter
        private String desc;
        @Getter
        private Integer code;
    }

### 创建controller ###

package com.hawk.yoga.controller;
    
    import com.hawk.yoga.common.result.YogaResult;
    import com.hawk.yoga.model.User;
    import com.hawk.yoga.model.dto.UserDto;
    import com.hawk.yoga.service.UserService;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.web.bind.annotation.RequestMapping;
    import org.springframework.web.bind.annotation.RequestMethod;
    import org.springframework.web.bind.annotation.RestController;
    
    /**
     * @Author:
     * @Description: demo
     * @Date: Create in  2019/7/13
     */
    @RestController
    @RequestMapping("/user")
    public class TestController {
    
        @Autowired
        private UserService userService;
    
        @RequestMapping(value = "/add", method = RequestMethod.GET)
        public YogaResult addUser(UserDto userDto) {
    
            userService.add(userDto);
            return YogaResult.ok();
        }
    
        @RequestMapping(value = "/find", method = RequestMethod.GET)
        public YogaResult<User> addUser(String name) {
            User userByName = userService.findUserByName(name);
            return YogaResult.ok(userByName);
        }
    
    }

### service ###

package com.hawk.yoga.service;
    
    import com.hawk.yoga.mapper.UserMapper;
    import com.hawk.yoga.model.User;
    import com.hawk.yoga.model.dto.UserDto;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    
    /**
     * @Author: 
     * @Description:
     * @Date: Create in  2019/7/13
     */
    @Service
    public class UserServiceImpl implements UserService{
    
        @Autowired
        private UserMapper userMapper;
        @Override
        public void add(UserDto userDto) {
            userMapper.add("yoga", 22, 3000.0);
        }
    
        @Override
        public User findUserByName(String name) {
            return userMapper.findUserByName(name);
        }
    
    }

public interface UserService {
        /**
         * add
         */
        void add(UserDto userDto);
    
        /**
         *
         * @param name
         * @return
         */
        User findUserByName(String name);
    }

### mapper ###

@Mapper
    public interface UserMapper {
    
        /**
         * @param name
         * @param age
         * @param money
         * @return
         */
        @Insert("INSERT INTO user(name, age,money) VALUES(#{name}, #{age}, #{money})")
        Integer add(@Param("name") String name, @Param("age") Integer age, @Param("money") Double money);
    
        /**
         * @param name
         * @return
         */
        User findUserByName(String name);
    }

添加方法使用的是注解，简单应用推荐第一种，一般使用第二中通过xml配置

### 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.hawk.yoga.mapper.UserMapper">
    
        <select id="findUserByName" parameterType="java.lang.String" resultType="com.hawk.yoga.model.User">
            SELECT * FROM user WHERE name = #{name}
        </select>
    </mapper>

实际应用中不要用\*，会导致扫描全表。

### 配置文件 application.properties ###

server.port=8520
    spring.datasource.url=jdbc:mysql://127.0.0.1:3306/item?useUnicode=true&characterEncoding=utf8&useSSL=false&serverTimezone=GMT%2B8
    spring.datasource.username=root
    spring.datasource.password=root
    spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
    mybatis.mapper-locations=classpath:mapper/*.xml

### 数据库 ###

CREATE TABLE `user` (
      `id` int(13) NOT NULL AUTO_INCREMENT COMMENT '主键',
      `name` varchar(33) DEFAULT NULL COMMENT '姓名',
      `age` int(3) DEFAULT NULL COMMENT '年龄',
      `money` double DEFAULT NULL COMMENT '账户余额',
      PRIMARY KEY (`id`)
    ) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=utf8

到此项目已经完成，可以运行起来了，其中有一点不规范的地方就是service哪里，我直接写死了数据，只是为了测试起来方便，最后一点在启动应用上加一个注解：扫描mapper  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3UwMTQ0OTI2NjU_size_16_color_FFFFFF_t_70 5]  
是不是很轻松呢，感谢你的阅读，不当之处请指教。

[add]: /images/20211210/ce1a4488890646da9d2381670a3398f7.png
[find]: /images/20211210/9378ad9139394561bf7db4d2e087204f.png
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