Spring整合Mybatis

一、使用Mybatis基本步骤

• 编写实体类
• 编写核心配置文件
• 编写接口
• 编写Mapper.xml
• 测试

二、整合Mybatis

导入依赖

• mybatis
• mysql数据库
• spring相关的
• aop织入
• mybatis-spring

<dependencies>
    <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.3.7</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.3.24</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.30</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.11</version>
    </dependency>
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>2.0.2</version>
    </dependency>
    <dependency>
        <groupId>org.aspectj</groupId>
        <artifactId>aspectjweaver</artifactId>
        <version>1.9.4</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.13.2</version>
        <scope>test</scope>
    </dependency>
</dependencies>

2.1 方法一（推荐）

2.1.1 编写数据源配置

<!--DataSource：使用Spring数据源替换Mybatis数据源配置-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
    <property name="url" value="jdbc:mysql://localhost:3306/test?useSSL=false&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
    <property name="username" value="root"/>
    <property name="password" value="nc20011019"/>
</bean>

2.1.2 sqlSessionFactory

<!--sqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <property name="dataSource" ref="dataSource" />
    <!--绑定Mybatis配置文件-->
    <property name="configLocation" value="classpath:mybatis-config.xml"/>
    <property name="mapperLocations" value="classpath:com/nichu/mapper/*.xml"/>
</bean>

2.1.3 sqlSessionTemplete

<!--sqlSessionTemplete:就是我们使用的sqlSession-->
<bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
    <!--只能使用构造注入sqlSessionFactory，因为他没有set方法-->
    <constructor-arg index="0" ref="sqlSessionFactory"/>
</bean>

2.1.4 需要给接口加实现类

public class StudentMapperImpl implements StudentMapper{
    private SqlSessionTemplate sqlSession;
    public void setSqlSession(SqlSessionTemplate sqlSession) {
        this.sqlSession = sqlSession;
    }
    @Override
    public List<Student> getStudentList() {
        StudentMapper mapper = sqlSession.getMapper(StudentMapper.class);
        return mapper.getStudentList();
    }
}

2.1.5 将自己写的实现类注入到Spring中

<bean id="studentMapper" class="com.nichu.mapper.StudentMapperImpl">
    <property name="sqlSession" ref="sqlSession"/>
</bean>

2.1.6 测试

public static void main(String[] args) {
  ApplicationContext context = new ClassPathXmlApplicationContext("spring-mybatis.xml");
  StudentMapper studentMapper = context.getBean("studentMapper", StudentMapper.class);
  for (Student student : studentMapper.getStudentList()) {
  System.out.println(student);
  }
}

2.2 方法二

2.2.1 配置数据源和sqlSessionFactory

<!--DataSource：使用Spring数据源替换Mybatis数据源配置-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
    <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
    <property name="url" value="jdbc:mysql://localhost:3306/test?useSSL=false&amp;useUnicode=true&amp;characterEncoding=UTF-8"/>
    <property name="username" value="root"/>
    <property name="password" value="nc20011019"/>
</bean>

<!--sqlSessionFactory-->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
    <property name="dataSource" ref="dataSource" />
    <!--绑定Mybatis配置文件-->
    <property name="configLocation" value="classpath:mybatis-config.xml"/>
    <property name="mapperLocations" value="classpath:com/nichu/mapper/*.xml"/>
</bean>

2.2.2 编写接口实现类

//继承SqlSessionDaoSupport类可以直接getSqlSession()
public class StudentMapperImpl2 extends SqlSessionDaoSupport implements StudentMapper{
    @Override
    public List<Student> getStudentList() {
        return getSqlSession().getMapper(StudentMapper.class).getStudentList();
    }
}

2.2.3 Spring中注入sqlSessionFactory

<bean id="studentMapper2" class="com.nichu.mapper.StudentMapperImpl2">
    <property name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>