MyBatis-Spring连接

Mybatis-Spring

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1.准备JAR包

略

2.编写配置文件

在类路径下建立下面几个文件

# db.properties
jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/mybatis
jdbc.username=root
jdbc.password=
jdbc.maxTotal=30
jdbc.maxIdle=10
jdbc.initialSize=5

<!--applicationContext.xml--> 
<context:property-placeholder location="classpath:db.properties"/>
    <bean id="dataSource"
          class="org.apache.commons.dbcp2.BasicDataSource">
        <!--数据库驱动-->
        <property name="driverClassName" value="${jdbc.driver}"/>
        <!--连接数据库的 url -->
        <property name="url" value="${jdbc.url}"/>
        <!--连接数据库的用户名-->
        <property name="username" value="${jdbc.username}"/>
        <!--连接数据库的密码-->
        <property name="password" value="${jdbc.password}"/>
        <!--最大连接数-->
        <property name="maxTotal" value="${jdbc.maxTotal}"/>
        <!--最大空闲连接-->
        <property name="maxIdle" value="${jdbc.maxIdle}"/>
        <!--初始化连接数-->
        <property name="initialSize" value="${jdbc.initialSize}"/>
    </bean>
    <!--Spring 事务管理（需要配置具体管理的数据源）-->
    <bean id="transactionManager" class=
            "org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    <!--事务开启注解-->
    <tx:annotation-driven transaction-manager="transactionManager"/>
    <!--配置MyBatis工厂-->
    <bean id="sqlSessionFactory"
          class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
    </bean>

<!--mybatis-config.xml-->
<configuration>
    <typeAliases>
        <!--配置别名-->
        <package name="com.itheima.po"/>
    </typeAliases>
    <mappers>
    </mappers>
</configuration>

3.Mapper接口整合

1.编写Mapper文件和Mapper接口

<!--CustomerMapper.xml-->
<mapper namespace="com.itheima.mapper.CustomerMapper">
    <select id="findCustomerById" parameterType="Integer"
            resultType="Customer">
        select * from t_customer where id=#{id}
    </select>
</mapper>

// CustomerMapper.java
public interface CustomerMapper {
    public Customer findCustomerById(Integer id);
}

2.主配置文件中添加映射文件

<mappers>
	<mapper resource="com/itheima/mapper/CustomerMapper.xml"/>
</mappers>

3.将接口包装为MapperFactoryBean

<bean id="customerMapper"-->
	class="org.mybatis.spring.mapper.MapperFactoryBean">
<property name="mapperInterface"
	value="com.itheima.mapper.CustomerMapper"/>
<property name="sqlSessionFactory" ref="sqlSessionFactory"/>
</bean>

MapperFactoryBean会根据传过来的接口，生成对应的类

4.测试

@Test
public void findCustomerByIdMapperTest(){
	ApplicationContext act =
		new ClassPathXmlApplicationContext("applicationContext.xml");
	CustomerMapper customerMapper = act.getBean(CustomerMapper.class);
	Customer customer = customerMapper.findCustomerById(1);
	System.out.println(customer);
}

5.实际开发

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
	<property name="basePackage" value="com.itheima.mapper"/>
</bean>

Spring中加入后不需要 2，3步骤配置即可自动扫描完成

4.事务测试

<!--applicationContext.xml中加入注解扫描-->
<context:component-scan base-package="com.itheima.service"/>

编写事务接口的实现类

@Service
@Transactional
public class CustomerServiceImpl implements CustomerService{
    @Autowired
    private CustomerMapper customerMapper;
    @Override
    public void addCustomer(Customer customer) {
        this.customerMapper.addCustomer(customer);
        int i=1/0; //制造异常
    }
}

//测试
@Test
public void findCustomerByIdDaoTest(){
    ApplicationContext act =
            new ClassPathXmlApplicationContext("applicationContext.xml");
    CustomerDao customerDao;
    //customerDao = (CustomerDao) act.getBean("customerDao");
    customerDao = act.getBean(CustomerDao.class);
    Customer customer = customerDao.findCustomerById(1);
    System.out.println(customer);
}