Spring-Mybatis

　　MyBatis-Spring 会帮助你将 MyBatis 代码无缝地整合到 Spring 中。它将允许 MyBatis 参与到 Spring 的事务管理之中，创建映射器 mapper 和 SqlSession 并注入到 bean 中，以及将 Mybatis 的异常转换为 Spring 的 DataAccessException。 最终，可以做到应用代码不依赖于 MyBatis，Spring 或 MyBatis-Spring

　

　一、SpringBoot-Mybatis

　　1、jar包依赖

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.49</version>
        </dependency>
        <!--mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.0</version>
        </dependency>

　　2、application.properties中配置数据库连接信息

#数据库信息
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/test
spring.datasource.username=yang
spring.datasource.password=yang
# mapper xml文件路径
mybatis.mapper-locations=classpath:mapper/*Mapper.xml

　　3、启动类上添加MapperScan注解，扫描Mapper接口

import org.mybatis.spring.annotation.MapperScan;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@MapperScan(basePackages = "com.yang.spbo.mybatis.mapper")
@SpringBootApplication
public class SpboMybatisApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpboMybatisApplication.class, args);
    }

}

　　4、定义Mapper接口，@Mapper注解可省略

@Mapper
public interface WeiboFansMapper {
    int insertWeiboFans(WeiboFans weiboFans);
}

　　5、Mapper.xml，放在指定的classpath:mapper/*Mapper.xml下

  注意：Mapper.xml若放在依赖的包resources下，如common包，则路径要设置为 classpath*:mapper/*Mapper.xml

  若mapper路径下还有子路径，则设置为classpath*:mapper/**/*Mapper.xml

<?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.yang.spbo.mybatis.mapper.WeiboFansMapper">

    <insert id="insertWeiboFans" parameterType="com.yang.spbo.mybatis.domain.WeiboFans">
        insert into weibo_fans
        (weibo_id,`name`,location,gender,profile,`desc`)
        VALUE
        (#{weiboId},#{name},#{location},#{gender},#{profile},#{desc})
    </insert>

</mapper>

　　6、使用Mapper操作数据库

    @Resource
    private WeiboFansMapper weiboFansMapper;

    @Test
    void insertWeiboFansTest() {
        WeiboFans weiboFans = new WeiboFans();
        weiboFans.setId(745234093L);
        weiboFans.setGender("m");
        weiboFans.setName("杨豈Y");
        weiboFans.setLocation("江苏 南京");
        try {
            weiboFansMapper.insertWeiboFans(weiboFans);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

 

　　补充

　　　　直接使用sqlSession：

@Component
public class CityDao {

  private final SqlSession sqlSession;

  public CityDao(SqlSession sqlSession) {
    this.sqlSession = sqlSession;
  }

  public City selectCityById(long id) {
    return this.sqlSession.selectOne("selectCityById", id);
  }

}

　　　　application.properties可用的配置：

Property	Description
config-location	Location of MyBatis xml config file.
check-config-location	Indicates whether perform presence check of the MyBatis xml config file.
mapper-locations	Locations of Mapper xml config file.
type-aliases-package	Packages to search for type aliases. (Package delimiters are “,; \t\n”)
type-aliases-super-type	The super class for filtering type alias. If this not specifies, the MyBatis deal as type alias all classes that searched from type-aliases-package.
type-handlers-package	Packages to search for type handlers. (Package delimiters are “,; \t\n”)
executor-type	Executor type: SIMPLE, REUSE, BATCH
default-scripting-language-driver	The default scripting language driver class. This feature requires to use together with mybatis-spring 2.0.2+.
configuration-properties	Externalized properties for MyBatis configuration. Specified properties can be used as placeholder on MyBatis config file and Mapper file. For detail see the MyBatis reference page.
lazy-initialization	Whether enable lazy initialization of mapper bean. Set true to enable lazy initialization. This feature requires to use together with mybatis-spring 2.0.2+.
mapper-default-scope	Default scope for mapper bean that scanned by auto-configure. This feature requires to use together with mybatis-spring 2.0.6+.
configuration.*	Property keys for Configuration bean provided by MyBatis Core. About available nested properties see the MyBatis reference page. NOTE: This property cannot be used at the same time with the config-location.
scripting-language-driver.thymeleaf.*	Property keys for ThymeleafLanguageDriverConfig bean provided by MyBatis Thymeleaf. About available nested properties see the MyBatis Thymeleaf reference page.
scripting-language-driver.freemarker.*	Properties keys for FreeMarkerLanguageDriverConfig bean provided by MyBatis FreeMarker. About available nested properties see the MyBatis FreeMarker reference page. This feature requires to use together with mybatis-freemarker 1.2.0+.
scripting-language-driver.velocity.*	Properties keys for VelocityLanguageDriverConfig bean provided by MyBatis Velocity. About available nested properties see the MyBatis Velocity reference page. This feature requires to use together with mybatis-velocity 2.1.0+.

　　　　或者不在application.properties中配置，而是使用自定的Java配置：

@Configuration
public class MyBatisConfig {
  @Bean
  ConfigurationCustomizer mybatisConfigurationCustomizer() {
    return new ConfigurationCustomizer() {
      @Override
      public void customize(Configuration configuration) {
        // customize ...
      }
    };
  }
}

　　　　 MyBatis-Spring-Boot-Starter 会自动搜索实现 ConfigurationCustomizer 接口的 bean，并调用自定义 MyBatis 配置的方法。

 

 

　　

　二、Spring-Mybatis

　　1、jar包依赖

        <!--mysql-connect-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <dependency>
            <groupId>commons-dbcp</groupId>
            <artifactId>commons-dbcp</artifactId>
            <version>1.4</version>
        </dependency>
        <!--mybatis-spring-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.6</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
            <scope>compile</scope>
        </dependency>
        <!--事务-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

　　2、MySQL连接信息配置 mysql.properties

jdbc.url=jdbc:mysql://127.0.0.1:3306/database_name?useUnicode=true&characterEncoding=utf-8&autoReconnect=true&useSSL=true
jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.username=root
jdbc.password=root

　　3、mybatis-config.xml Mybatis配置文件，可省略

　　4、数据源配置

  注意：如果存在多个数据源的情况，需要配置多个DataSourceConfig，在每个DataSourceConfig上面basePackages扫描不同的Mapper接口，不同包下面的Mapper即可使用不同的数据源

import org.apache.commons.dbcp.BasicDataSource;
import org.apache.ibatis.session.ExecutorType;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.SqlSessionTemplate;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;

/**
 * @PropertySource 读取mysql.propertis中的配置保存到运行的环境变量Environment中
 * @MapperScan
 *  basePackage：用于扫描MyBatis Mapper接口的基本包。注意，只有具有至少一个方法的接口才会被注册
 *  sqlSessionTemplateRef：当有多个数据源时，用来指定在spring上下文中有多个sqlessiontemplate时使用哪个sqlessiontemplate
 */
@MapperScan(basePackages = "com.yang.spmy.springmybatis.mapper",sqlSessionTemplateRef = "sqlSessionTemplate")
@Configuration
@PropertySource("classpath:mysql.properties")
public class DataSourceConfig {

    @Value("${jdbc.driver}")
    private String diverClassName;

    @Value("${jdbc.url}")
    private String url;

    @Value("${jdbc.username}")
    private String username;

    @Value("${jdbc.password}")
    private String password;

    @Bean
    public DataSource dataSource() {
        BasicDataSource dataSource = new BasicDataSource();
        dataSource.setDriverClassName(diverClassName);
        dataSource.setUrl(url);
        dataSource.setUsername(username);
        dataSource.setPassword(password);
        dataSource.setMaxActive(10);
        dataSource.setMaxIdle(2);
        dataSource.setMinIdle(1);
        dataSource.setMaxWait(6000);
        // 用来验证连接是否生效的sql语句
        dataSource.setValidationQuery("SELECT 1");
        // 从池中获取连接前进行验证
        dataSource.setTestOnBorrow(true);
        // 向池中还回连接前进行验证
        dataSource.setTestOnReturn(false);
        // 连接空闲时验证
        dataSource.setTestWhileIdle(true);
        // 运行判断连接超时任务的时间间隔，单位为毫秒，默认为-1，即不执行任务
        dataSource.setTimeBetweenEvictionRunsMillis(40000);
        // 连接的超时时间，默认为半小时
        dataSource.setMinEvictableIdleTimeMillis(50000);
        return dataSource;
    }

    @Bean
    public SqlSessionFactory sqlSessionFactory() throws Exception {
        SqlSessionFactoryBean sqlSessionFactoryBean = new SqlSessionFactoryBean();
        PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
        // mapper xml文件，有两种方式 ①：MyBatis的XML配置文件中的<mappers>中指定XML文件的类路径 ②：设置工厂bean的mapperLocations属性
        sqlSessionFactoryBean.setMapperLocations(resolver.getResources("classpath:/mapper/**/*Mapper.xml"));
        // 数据源
        sqlSessionFactoryBean.setDataSource(dataSource());
//        Resource config = new ClassPathResource("mybatis-config.xml");
        // MyBatis XML配置文件路径
//        sqlSessionFactoryBean.setConfigLocation(config);
        return sqlSessionFactoryBean.getObject();
    }

    @Bean("sqlSessionTemplate")
    public SqlSessionTemplate sqlSessionTemplate() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory());
    }

    @Bean("batchSqlSessionTemplate")
    public SqlSessionTemplate batchSqlSessionTemplate() throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory(), ExecutorType.BATCH);
    }

    @Bean("dataSourceTransactionManager")
    public DataSourceTransactionManager transactionManager() {
        DataSourceTransactionManager dataSourceTransactionManager = new DataSourceTransactionManager();
        // Spring容器管理事务，指定数据源
        dataSourceTransactionManager.setDataSource(dataSource());
        return dataSourceTransactionManager;
    }
    
}

　　配置说明：

    sqlSession和事务与数据源关系：

    

 

  5、定义Mapper接口，@Mapper注解可省略

@Mapper
public interface TestMapper {
    Category selectById(Long id);
}

　　6、Mapper.xml，放在指定的classpath:mapper/*Mapper.xml下

<?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.yang.spmy.springmybatis.mapper.TestMapper">

    <sql id="column">
        `id`, `parent`, `name`, `type`, `level`, `update_time`, `create_time`
    </sql>

    <select id="selectById" resultType="com.yang.spmy.springmybatis.model.Category">
        select
        <include refid="column"/>
        from `category` where `id` = #{id}
    </select>

</mapper>

　　7、使用Mapper操作数据库

    @Autowired
    private TestMapper testMapper;

    @Test
    void categoryTest() {
        Category category = testMapper.selectById(15L);
        System.out.println(category);
    }

 

 

 

 

 

 附录：

　　Spring-Mybatis官方文档：http://mybatis.org/spring/zh/index.html

　　SpringBoot-Mybatis官方文档：http://mybatis.org/spring-boot-starter/mybatis-spring-boot-autoconfigure/

　　

 

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