[Java知识库]Spring整合MyBatis

1 新建一个maven工程

2 配置mybatis相关

? ? ?1? 添加mybatis依赖

<!-- MyBatis依赖 -->
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.27</version>
</dependency>

<dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.5.7</version>
</dependency>

2??新建mybatis-config.xml配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>

</configuration>

3 添加Lombok、junit依赖

<dependency>
<groupId>org.projectlombok</groupId>
    <artifactId>lombok</artifactId>
    <version>1.18.22</version>
</dependency>
<dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.13.1</version>
    <scope>test</scope>
</dependency>

?3 部署Spring

框架

? ? ? 1? 添加依赖

<!-- Spring依赖 -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>5.3.18</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>5.3.18</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.3.18</version>
        </dependency>

? ?2? ??创建applicationContext.xml配置文件

<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans 
        https://www.springframework.org/schema/beans/spring-beans.xsd
         http://www.springframework.org/schema/aop 
         https://www.springframework.org/schema/aop/spring-aop.xsd
         http://www.springframework.org/schema/context
         https://www.springframework.org/schema/context/spring-context.xsd">

</beans>

4?Spring整合MyBatis?

? ? ?1 添加整合依赖

 <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.7</version>
        </dependency>

? ?2??.配置数据源（Druid）

? ? ? ??添加druid依赖

<!-- druid依赖 -->
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.2.8</version>
</dependency>

? ? ??创建druid.properties文件

druid.driver=com.mysql.cj.jdbc.Driver
druid.url=jdbc:mysql://localhost:3306/ssm?characterEncoding=utf-8
druid.username=root
druid.password=root

## 连接池参数
druid.pool.init=1
druid.pool.minIdle=3
druid.pool.maxActive=20
druid.pool.maxWait=30000

?Spring配置文件中配置DruidDataSource

?

 <!--加载druid.properties文件-->
 <context:property-placeholder location="classpath:druid.properties"/>
 <!--数据源DataSource的创建-->
 <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
     <property name="driverClassName" value="${druid.driver}"/>
     <property name="url" value="${druid.url}"/>
     <property name="username" value="${druid.username}"/>
     <property name="password" value="${druid.password}"/>

     <property name="initialSize" value="${druid.pool.init}"/>
     <property name="minIdle" value="${druid.pool.minIdle}"/>
     <property name="maxActive" value="${druid.pool.maxActive}"/>
     <property name="maxWait" value="${druid.pool.maxWait}"/>
 </bean>

创建SqlSessionFactory

<!--MyBatis的SqlSessionFactory对象的创建-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <!--配置数据源-->
    <property name="dataSource" ref="dataSource"/>
    <!--配置Mapper文件路径-->
    <property name="mapperLocations" value="classpath:mappers/*Mapper.xml"/>
    <!--配置需要定义别名的实体类的包-->
    <property name="typeAliasesPackage" value="com.gyh.pojo"/>
    <!--配置MyBatis的配置文件-->
    <property name="configLocation" value="classpath:mybatis-config.xml"/>
</bean>

创建Mapper

<!--加载dao包中的所有接口，通过sqlSessionFactory获取sqlSession对象，然后创建所有的dao接口并存储在Spring容器中-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <property name="basePackage" value="com.gyh.dao"/>
    </bean>

使用示例

public interface DepMapper {
    List<Dep> selectByExample();
}

<?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.dao.DepMapper" >
  <select id="selectByExample" resultType="com.pojo.Dep" >
    select  * from dep
  </select>

</mapper>

public class test {
    @Test
    public void selectByExample() {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        //UserDao userDao = context.getBean("userDao", UserDao.class);
        DepMapper depMapper = context.getBean("depMapper", DepMapper.class);
        List<Dep> deps = depMapper.selectByExample();
        System.out.println("deps===" + deps);
    }


}