SpringBoot 2.0集成MySQL+mybatis+Druid配置_springboot如何配置mybatis,使用mysql和druid框架

本文采用的springboot版本为2.1.4，mybatis版本为1.3.2，Druid版本为1.1.10

springboot项目骨架生成不在赘述，idea可以用spring initializr生成，或者直接到spring官网https://start.spring.io生成，下载之后导入到idea中。

1.引入jar包，pom文件如下：

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>springbucks</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springbucks</name>
    <description>Demo project for Spring Boot</description>
 
    <properties>
        <java.version>1.8</java.version>
    </properties>
 
    <dependencies>
 
        <!--打开监控-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <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>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
 
        <!-- druid数据源 -->
        <!-- https://mvnrepository.com/artifact/com.alibaba/druid -->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.1.10</version>
        </dependency>
 
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>
 
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
 
</project>

pom中引入了actuator监控、druid、mybatis、lombok、mysql等依赖

2.application.yml配置如下：

server:
    port: 8088
spring:
    application:
        name: spring-bucks
    datasource:
        druid:
            driver-class-name: com.mysql.cj.jdbc.Driver
            url: jdbc:mysql://localhost/demo?characterEncoding=UTF-8&useSSL=false
            username: developer
            password: developer12321
            filters: stat,wall
            initial-size: 3
            min-idle: 1
            max-active: 20
            test-on-borrow: false
            test-on-return: false
            test-while-idle: true
            validation-query: select 'x'
            max-wait: 6000
            pool-prepared-statements: true
            time-between-eviction-runs-millis: 60000
            min-evictable-idle-time-millis: 60000
            web-stat-filter:
                enabled: true
                url-pattern: "/*"
            stat-view-servlet:
                enabled: true
                url-pattern: /druid/*
                reset-enable: false
                login-username: admin
                login-password: admin
mybatis:
    configuration:
        map-underscore-to-camel-case: true
    type-handlers-package: com.example.springbucks.handler
    type-aliases-package: com.example.springbucks.model
    mapper-locations: classpath:mappers/*.xml
logging:
    level:
        com:
            example:
                springbucks:
                    dao: debug
 
management:
    endpoints:
        web:
            exposure:
                include: "*"

druid各项配置建议参考durid官方文档https://github.com/alibaba/druid/wiki

这里重点说几个mybatis的配置

map-underscore-to-camel-case: true

这项配置可以实现数据库表字段和类变量名的自动映射，例如列名create_time会自动映射到字段名createTime，省去写ResultMap的麻烦，这里建议大家开发时都能遵守一定的规范，可以提高效率

type-aliases-package: com.example.springbucks.model

大家知道在mapper文件中写ParameterType和ResultType时必须是全包名，很不便利，这个配置只需要写实体类的别名就行了，但是在实体类上要加入注解。如下，在mapper中，com.example.springbucks.model.Coffee可以直接用coffee代替

package com.example.springbucks.model;
 
import lombok.*;
import lombok.experimental.Accessors;
import org.apache.ibatis.type.Alias;
import org.joda.money.Money;
import org.springframework.data.mongodb.core.mapping.Document;
 
import java.io.Serializable;
 
/**
 * @author Gary
 * @className Coffee
 * @description TODO
 * @date 2019-04-13 19:06
 **/
 
@Document
@Data
@ToString(callSuper = true)
@EqualsAndHashCode(callSuper = false)
@NoArgsConstructor
@AllArgsConstructor
@Accessors(chain = true)
@Alias("coffee")
public class Coffee extends BaseModel implements Serializable {
 
    private String name;
 
    private Money price;
 
}

    <select id="search" parameterType="coffee" resultType="coffee">
        SELECT
            *
        FROM
            t_coffee t
        <where>
            <if test="name != null and name != ''">
                AND t.NAME LIKE LOWER( '%${name}%' )
            </if>
            <if test="price != null">
                AND t.price = #{price}
            </if>
        ORDER BY id
        </where>
    </select>

mapper-locations: classpath:mappers/*.xml

指定mapper文件的路径

3.启动类配置

@MapperScan("com.example.springbucks.dao")

启动类加入@MapperScan注解之后，spring会到相应的包下面扫描，不需要在每个dao接口里加@Mapper注解

4.dao

package com.example.springbucks.dao;
 
import com.example.springbucks.model.Coffee;
import org.apache.ibatis.annotations.*;
import org.apache.ibatis.session.RowBounds;
 
import java.util.List;
 
/**
 * TODO
 *
 * @author Gary
 *
 * @date 2019-04-13 19:24
 */
public interface CoffeeDao {
 
    /**
     * @description: 新增coffee
     * @author Gary
     * @param coffee
     *
     * @return java.lang.Long
     * @date 2019-04-07 20:59
     */
    @Insert("insert into t_coffee (name, price, create_time, update_time) " +
            "values (#{name}, #{price}, now(), now())")
    @Options(useGeneratedKeys = true)
    Long save(Coffee coffee);
 
    /**
     * 根据id查询coffee
     * @description:
     * @author Gary
     * @param id
     *
     * @return com.example.mybatisdemo.model.Coffee
     * @date 2019-04-07 20:59
     */
    @Select("select * from t_coffee where id = #{id}")
    @Results({
            @Result(id = true, column = "id", property = "id")
    })
    Coffee findById(Long id);
 
    /**
     * 分页查询
     *
     * @description: TODO
     * @author Gary
     * @param rowBounds
     *
     * @return java.util.List<com.example.mybatisdemo.model.Coffee>
     * @date 2019-04-07 21:13
     */
    @Select("select * from t_coffee order by id")
    List<Coffee> findAllWithRowBounds(RowBounds rowBounds);
 
    List<Coffee> search(Coffee coffee);
 
}

<?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.springbucks.dao.CoffeeDao">
 
    <select id="search" parameterType="coffee" resultType="coffee">
        SELECT
            *
        FROM
            t_coffee t
        <where>
            <if test="name != null and name != ''">
                AND t.NAME LIKE LOWER( '%${name}%' )
            </if>
            <if test="price != null">
                AND t.price = #{price}
            </if>
        ORDER BY id
        </where>
    </select>
 
</mapper>

5.service

package com.example.springbucks.service;
 
import com.example.springbucks.model.Coffee;
import org.apache.ibatis.annotations.Param;
 
import java.util.List;
 
/**
 * @author Gary
 * @className CoffeeService
 * @description TODO
 * @date 2019-04-13 19:16
 **/
public interface CoffeeService {
 
    Long save(Coffee coffee);
 
    Coffee findById(Long id);
 
    List<Coffee> findAllByPage(@Param("pageNum") int pageNum,
                               @Param("pageSize") int pageSize);
 
    List<Coffee> search(Coffee coffee);
 
}

package com.example.springbucks.service.impl;
 
import com.example.springbucks.dao.CoffeeDao;
import com.example.springbucks.model.Coffee;
import com.example.springbucks.service.CoffeeService;
import org.apache.ibatis.session.RowBounds;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
 
import java.util.List;
 
/**
 * @author Gary
 * @className CoffeeServiceImpl
 * @description TODO
 * @date 2019-04-13 19:25
 **/
@Service("coffeeService")
public class CoffeeServiceImpl implements CoffeeService {
 
    @Autowired
    private CoffeeDao coffeeDao;
 
    @Override
    public Long save(Coffee coffee) {
        return coffeeDao.save(coffee);
    }
 
    @Override
    public Coffee findById(Long id) {
        return coffeeDao.findById(id);
    }
 
    @Override
    public List<Coffee> findAllByPage(int pageNum, int pageSize) {
        RowBounds rowBounds = new RowBounds(pageNum, pageSize);
        return coffeeDao.findAllWithRowBounds(rowBounds);
    }
 
    @Override
    public List<Coffee> search(Coffee coffee) {
        return coffeeDao.search(coffee);
    }
 
}

6.启动项目之后可到http://localhost:8088/druid/login.html页面查看druid的相关信息