SpringBoot+mybatis+mysql 多数据源配置及

多数据源配置

创建一个Spring配置类，定义两个DataSource用来读取application.properties中的不同配置。

配置文件

application.properties

mybatis.config-locations=classpath:mybatis/mybatis-config.xml

#datasource
spring.devtools.remote.restart.enabled=false

#data source1
spring.datasource.test1.driverClassName=com.mysql.jdbc.Driver
spring.datasource.test1.url=jdbc:mysql://127.0.0.1:3306/test_msg1
spring.datasource.test1.username=root
spring.datasource.test1.password=root

#data source2
spring.datasource.test2.driverClassName=com.mysql.jdbc.Driver
spring.datasource.test2.url=jdbc:mysql://127.0.0.1:3306/test_msg2
spring.datasource.test2.username=root
spring.datasource.test2.password=root

mybatis配置文件
针对两个数据源，做两个mybatis的mapper配置文件
resource/mybatis/mapper/test1/UserMapper1.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.chun.mapper.test1.User1Mapper" >
    <resultMap id="BaseResultMap" type="com.chun.entity.UserEntity" >
        <id column="id" property="id" jdbcType="BIGINT" />
        <result column="userName" property="userName" jdbcType="VARCHAR" />
        <result column="passWord" property="passWord" jdbcType="VARCHAR" />
        <result column="user_sex" property="userSex" javaType="com.chun.enums.UserSexEnum"/>
        <result column="nick_name" property="nickName" jdbcType="VARCHAR" />
    </resultMap>

    <sql id="Base_Column_List" >
        id, userName, passWord, user_sex, nick_name
    </sql>

    <select id="getAll" resultMap="BaseResultMap"  >
        SELECT
        <include refid="Base_Column_List" />
        FROM users
    </select>

    <select id="getOne" parameterType="java.lang.Long" resultMap="BaseResultMap" >
        SELECT
        <include refid="Base_Column_List" />
        FROM users
        WHERE id = #{id}
    </select>

    <insert id="insert" parameterType="com.chun.entity.UserEntity" >
        INSERT INTO
        users
        (userName,passWord,user_sex)
        VALUES
        (#{userName}, #{passWord}, #{userSex})
    </insert>

    <update id="update" parameterType="com.chun.entity.UserEntity" >
        UPDATE
        users
        SET
        <if test="userName != null">userName = #{userName},</if>
        <if test="passWord != null">passWord = #{passWord},</if>
        nick_name = #{nickName}
        WHERE
        id = #{id}
    </update>

    <delete id="delete" parameterType="java.lang.Long" >
        DELETE FROM
        users
        WHERE
        id =#{id}
    </delete>

</mapper>

resource/mybatis/mapper/test2/UserMapper2.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.chun.mapper.test2.User2Mapper" >
    <resultMap id="BaseResultMap" type="com.chun.entity.UserEntity" >
        <id column="id" property="id" jdbcType="BIGINT" />
        <result column="userName" property="userName" jdbcType="VARCHAR" />
        <result column="passWord" property="passWord" jdbcType="VARCHAR" />
        <result column="user_sex" property="userSex" javaType="com.chun.enums.UserSexEnum"/>
        <result column="nick_name" property="nickName" jdbcType="VARCHAR" />
    </resultMap>

    <sql id="Base_Column_List" >
        id, userName, passWord, user_sex, nick_name
    </sql>

    <select id="getAll" resultMap="BaseResultMap"  >
        SELECT
        <include refid="Base_Column_List" />
        FROM users
    </select>

    <select id="getOne" parameterType="java.lang.Long" resultMap="BaseResultMap" >
        SELECT
        <include refid="Base_Column_List" />
        FROM users
        WHERE id = #{id}
    </select>

    <insert id="insert" parameterType="com.chun.entity.UserEntity" >
        INSERT INTO
        users
        (userName,passWord,user_sex)
        VALUES
        (#{userName}, #{passWord}, #{userSex})
    </insert>

    <update id="update" parameterType="com.chun.entity.UserEntity" >
        UPDATE
        users
        SET
        <if test="userName != null">userName = #{userName},</if>
        <if test="passWord != null">passWord = #{passWord},</if>
        nick_name = #{nickName}
        WHERE
        id = #{id}
    </update>

    <delete id="delete" parameterType="java.lang.Long" >
        DELETE FROM
        users
        WHERE
        id =#{id}
    </delete>

</mapper>

启动类

Application

开启事务管理功能
在项目入口类，添加以下注解开启事务管理功能。

@EnableTransactionManagement(proxyTargetClass = true)

@SpringBootApplication
@EnableTransactionManagement(proxyTargetClass = true)   //开启事物管理功能
public class Application {
    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

数据源 datasource1 配置类

给其中一个数据源加上@Primary。因为在Spring Boot Jdbc的自动配置过程中，会对于开发者透明地使用dataSource进行一些相关配置，所以当有两个Datasource实现类时，Spring Boot将无法确定使用哪一个。
通过动态数据源构造SqlSessionFactory和事务管理器

package com.chun;


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.Qualifier;
import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Primary;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import javax.sql.DataSource;
/**
 *  数据源 datasource1 配置类
 * Created by chun on 2018/1/17.
 */
@Configuration
@MapperScan(basePackages = "com.chun.mapper.test1", sqlSessionTemplateRef  = "test1SqlSessionTemplate")
public class DataSource1Config {

    // @Primary 确定此数据源为master
    @Bean(name = "test1DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test1")
    @Primary
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "test1SqlSessionFactory")
    @Primary
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test1DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test1/*.xml"));
        return bean.getObject();
    }

    //配置事务管理器
    @Bean(name = "test1TransactionManager")
    @Primary
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test1DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test1SqlSessionTemplate")
    @Primary
    public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test1SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

}

数据源 datasource2 配置类

package com.chun;

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.Qualifier;
import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;

import javax.sql.DataSource;
/**
 *  数据源datasource2 配置类
 * Created by xiegaochun on 2018/1/17.
 */
@Configuration
@MapperScan(basePackages = "com.chun.mapper.test2", sqlSessionTemplateRef  = "test2SqlSessionTemplate")
public class DataSource2Config {

    @Bean(name = "test2DataSource")
    @ConfigurationProperties(prefix = "spring.datasource.test2")
    public DataSource testDataSource() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "test2SqlSessionFactory")
    public SqlSessionFactory testSqlSessionFactory(@Qualifier("test2DataSource") DataSource dataSource) throws Exception {
        SqlSessionFactoryBean bean = new SqlSessionFactoryBean();
        bean.setDataSource(dataSource);
        bean.setMapperLocations(new PathMatchingResourcePatternResolver().getResources("classpath:mybatis/mapper/test2/*.xml"));
        return bean.getObject();
    }

    @Bean(name = "test2TransactionManager")
    public DataSourceTransactionManager testTransactionManager(@Qualifier("test2DataSource") DataSource dataSource) {
        return new DataSourceTransactionManager(dataSource);
    }

    @Bean(name = "test2SqlSessionTemplate")
    public SqlSessionTemplate testSqlSessionTemplate(@Qualifier("test2SqlSessionFactory") SqlSessionFactory sqlSessionFactory) throws Exception {
        return new SqlSessionTemplate(sqlSessionFactory);
    }

}

定义dao层

mapper1

public interface User1Mapper {
    List<UserEntity> getAll();

    UserEntity getOne(Long id);

    void insert(UserEntity user);

    void update(UserEntity user);

    void delete(Long id);
}

mapper2

public interface User2Mapper {
    List<UserEntity> getAll();

    UserEntity getOne(Long id);

    void insert(UserEntity user);

    void update(UserEntity user);

    void delete(Long id);
}

Service层

service1

事物使用时只需在需要事务的方法添加注解@Transactional，并指定其value值即可。同样的，value值与相应的方法名相匹配即可。
@Transactional(value="test1TransactionManager",rollbackFor = Exception.class,timeout=36000)
其中参数rollbackFor =Exception.class说明针对Exception异常也进行回滚，如果不标注，则Spring 默认只有抛出 RuntimeException才会回滚事务

@Transactional配置事务有很多限制，如方法必须为public，同一个类中无该注解的方法调用有注解的方法事务不生效等。该注解还可以配置在接口类等地方

@Slf4j
@Service
public class User1Service {

    @Autowired
    private User1Mapper user1Mapper;

    public List<UserEntity> getUsers() {
        List<UserEntity> users=user1Mapper.getAll();
        return users;
    }

    public void delete(Long id) {
        user1Mapper.delete(id);
    }

    @Transactional(value="test1TransactionManager",rollbackFor = Exception.class,timeout=36000)  //说明针对Exception异常也进行回滚，如果不标注，则Spring 默认只有抛出 RuntimeException才会回滚事务
    public void updateTransactional(UserEntity user) {
        try{
            user1Mapper.delete(user.getId());
            int i= 1/0;
            user1Mapper.insert(user);
        }catch(Exception e){
            log.error("find exception!");
            throw e;   // 事物方法中，如果使用trycatch捕获异常后，需要将异常抛出，否则事物不回滚。
        }

    }
}

service2

@Service
public class User2Service {

    @Autowired
    private User2Mapper user2Mapper;

    public UserEntity getUser(Long id) {
        UserEntity user=user2Mapper.getOne(id);
        return user;
    }

    public void save(UserEntity user) {
        user2Mapper.insert(user);
    }


    public void update(UserEntity user) {
        user2Mapper.update(user);
    }
}