Spring Boot + Mybatis 全注解与XML

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全注解方式

Mybatis maper的全注解形式，不用dao接口，不用mapper的xml文件，都在一个类里面

/**
 * mybatis的dao接口和mapper配置文件的合体
 */
@Mapper
@Repository
public interface CustomerMapper {
    @Select("SELECT * FROM customers")
    List<Customer> findAll();
}

application.properties

server.port=8080
server.servlet.context-path=/boot

spring.mvc.view.prefix=/WEB-INF/views/
spring.mvc.view.suffix=.jsp

# mysql
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/shpun?useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=root

测试通过

@RunWith(SpringRunner.class)
@SpringBootTest
public class TestspringbootApplicationTests {

    @Autowired
    private CustomerMapper customerMapper;

    @Test
    public void testCustomerMapper(){
        System.out.println(customerMapper.findAll());
    }

}

xml方式

mybatis-config.xml mybatis的配置文件

<?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>

    <settings>
        <!-- 全局映射器启用缓存 -->
        <setting name="cacheEnabled" value="true"/>
        <!-- 允许JDBC支持生成的键 -->
        <setting name="useGeneratedKeys" value="true"/>
        <!-- 配置默认执行器 Reuse 重用预处理语句 -->
        <setting name="defaultExecutorType" value="REUSE"/>
        <!-- 全局启用延迟加载 -->
        <setting name="lazyLoadingEnabled" value="true"/>
        <!-- 设置超时时间，决定驱动等待一个数据库相应的时间 -->
        <setting name="defaultStatementTimeout" value="2500"/>
    </settings>

</configuration>

CustomerMapper.xml mapper的xml文件

<?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.shpun.dao.CustomerDao">
    <select id="selectAllCustomers" resultType="customer">
        select * from customers
    </select>
</mapper>

application.properties

server.port=8888
server.servlet.context-path=/yml

spring.mvc.view.prefix=/WEB-INF/views/
spring.mvc.view.suffix=.jsp

# mysql
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/shpun?useUnicode=true&characterEncoding=UTF-8
spring.datasource.username=root
spring.datasource.password=root

# mybatis
mybatis.type-aliases-package=com.shpun.bean
mybatis.config-location=classpath:mybatis/mybatis-config.xml
mybatis.mapper-locations=classpath:mapper/*.xml

dao 接口

@Mapper
@Repository
public interface CustomerDao{
    List<Customer> selectAllCustomers();
}

测试通过

@RunWith(SpringRunner.class)
@SpringBootTest
public class TestspringbootApplicationTests {

    @Autowired
    private CustomerDao customerDao;

    @Test
    public void testCustomerDao(){

        System.out.println(customerDao.selectAllCustomers());

    }
}

ps：

先前用xml的时候，提示错误找不到dao的bean，在dao上添加

@Mapper

如果是多个dao接口的话，每个都加比较麻烦，可以在SpringBootApplication的java类中添加

@MapperScan("com.shpun.dao")

参考 如何优雅的使用mybatis