说起多数据源，一般都来解决那些问题呢，主从模式或者业务比较复杂需要连接不同的分库来支持业务。我们项目是后者的模式，网上找了很多，大都是根据jpa来做多数据源解决方案，要不就是老的spring多数据源解决方案，还有的是利用aop动态切换，感觉有点小复杂，其实我只是想找一个简单的多数据支持而已，折腾了两个小时整理出来，供大家参考。
废话不多说直接上代码吧
配置文件
pom包就不贴了比较简单该依赖的就依赖，主要是数据库这边的配置：
mybatis.config-locations=classpath:mybatis/mybatis-config.xml spring.datasource.test1.driverClassName = com.mysql.jdbc.Driver spring.datasource.test1.url = jdbc:mysql://localhost:3306/test1?useUnicode=true&characterEncoding=utf-8 spring.datasource.test1.username = root spring.datasource.test1.password = root spring.datasource.test2.driverClassName = com.mysql.jdbc.Driver spring.datasource.test2.url = jdbc:mysql://localhost:3306/test2?useUnicode=true&characterEncoding=utf-8 spring.datasource.test2.username = root spring.datasource.test2.password = root
一个test1库和一个test2库，其中test1位主库，在使用的过程中必须制定主库，不然会报错。
数据源配置
@Configuration@MapperScan(basePackages = "com.neo.mapper.test1", sqlSessionTemplateRef = "test1SqlSessionTemplate")
public class DataSource1Config {
@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(); }
@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); } }
最关键的地方就是这块了，一层一层注入,先创建DataSource，在创建SqlSessionFactory在创建事务，最后包装到SqlSessionTemplate中。其中需要制定分库的mapper文件地址，以及分库到层代码
@MapperScan(basePackages = "com.neo.mapper.test1", sqlSessionTemplateRef = "test1SqlSessionTemplate")
这块的注解就是指明了扫描dao层，并且给dao层注入指定的SqlSessionTemplate。所有@Bean都需要按照命名指定正确。
dao层和xml层
dao层和xml需要按照库来分在不同的目录，比如：test1库dao层在com.neo.mapper.test1包下，test2库在com.neo.mapper.test1
public interface User1Mapper {
List<UserEntity> getAll();
UserEntity getOne(Long id);
void insert(UserEntity user);
void update(UserEntity user);
void delete(Long id);
}
xml层
<?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.neo.mapper.test1.User1Mapper" > <resultMap id="BaseResultMap" type="com.neo.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.neo.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.neo.entity.UserEntity" > INSERT INTO users (userName,passWord,user_sex) VALUES (#{userName}, #{passWord}, #{userSex})
</insert> <update id="update" parameterType="com.neo.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>
测试
测试可以使用SpringBootTest,也可以放到Controller中，这里只贴Controller层的使用
@RestControllerpublic class UserController {
@Autowired
private User1Mapper user1Mapper;
@Autowired
private User2Mapper user2Mapper;
@RequestMapping("/getUsers")
public List<UserEntity> getUsers() {
List<UserEntity> users=user1Mapper.getAll();
return users;
}
@RequestMapping("/getUser")
public UserEntity getUser(Long id) {
UserEntity user=user2Mapper.getOne(id);
return user;
}
@RequestMapping("/add")
public void save(UserEntity user) {
user2Mapper.insert(user);
}
@RequestMapping(value="update")
public void update(UserEntity user) {
user2Mapper.update(user);
}
@RequestMapping(value="/delete/{id}")
public void delete(@PathVariable("id") Long id) {
user1Mapper.delete(id);
}
}
最后源码地址在这里：https://github.com/ityouknow/spring-boot-starter
苹果手机代码会折行，建议苹果用户点击阅读原文查看，效果会更好一些。