springboot入门_多数据源

本文记录在springboot中配置多数据源，使用mybatis框架。

创建项目并添加依赖

 1 <dependency>
 2             <groupId>mysql</groupId>
 3             <artifactId>mysql-connector-java</artifactId>
 4             <scope>runtime</scope>
 5         </dependency>
 6 <dependency>
 7             <groupId>org.mybatis.spring.boot</groupId>
 8             <artifactId>mybatis-spring-boot-starter</artifactId>
 9             <version>1.3.2</version>
10         </dependency>

创建与数据库表对应的实体类对象

 1 public class City {
 2 
 3     private Long id;
 4     private String cityCode;
 5     private String cityName;
 6 
 7     //省略get和set方法
 8 
 9     @Override
10     public String toString(){
11         return "{id:"+this.getId()+",cityName:"+this.getCityName()+",cityCode:"+this.getCityCode()+"}";
12     }
13 
14 }

创建资源文件datasource.properties，并配置2个数据库连接信息

 1 #数据库1
 2 spring.datasource.one.url=jdbc:mysql://localhost:3306/test
 3 spring.datasource.one.username=root
 4 spring.datasource.one.password=123456
 5 spring.datasource.one.driver-class-name=com.mysql.jdbc.Driver
 6 #数据库2
 7 spring.datasource.two.url=jdbc:mysql://localhost:3306/test2
 8 spring.datasource.two.username=root
 9 spring.datasource.two.password=123456
10 spring.datasource.two.driver-class-name=com.mysql.jdbc.Driver

创建2个数据源配置类，完成数据源初始化

 1 @Configuration
 2 @PropertySource("classpath:datasource.properties")
 3 @MapperScan(basePackages = "org.allen.demo.dao.dbOne", sqlSessionTemplateRef = "sqlSessionTemplate1")
 4 public class DataSource1Config {
 5 
 6     @Autowired
 7     private Environment env;
 8 
 9     @Bean("dataSource1")
10     @Primary
11     public DataSource dataSource(){
12         System.out.println("初始化数据源1开始。。。");
13         HikariDataSource ds = new HikariDataSource ();
14         ds.setDriverClassName(env.getProperty("spring.datasource.one.driver-class-name").trim());
15         ds.setJdbcUrl(env.getProperty("spring.datasource.one.url").trim());
16         ds.setUsername(env.getProperty("spring.datasource.one.username").trim());
17         ds.setPassword(env.getProperty("spring.datasource.one.password").trim());
18         System.out.println("初始化数据源1结束。。。");
19         return ds;
20     }
21 
22     @Bean("sqlSessionFactory1")
23     @Primary
24     public SqlSessionFactory sqlSessionFactory(@Qualifier("dataSource1") DataSource dataSource) throws Exception {
25         SqlSessionFactoryBean sfb = new SqlSessionFactoryBean();
26         sfb.setDataSource(dataSource);
27         return sfb.getObject();
28     }
29 
30     @Bean("sqlSessionTemplate1")
31     @Primary
32     public SqlSessionTemplate sqlSessionTemplate(@Qualifier("sqlSessionFactory1") SqlSessionFactory sqlSessionFactory){
33         SqlSessionTemplate sft = new SqlSessionTemplate(sqlSessionFactory);
34         return sft;
35     }
36 
37     @Bean
38     @Primary
39     public DataSourceTransactionManager transactionManager(@Qualifier("dataSource1") DataSource dataSource){
40         return new DataSourceTransactionManager(dataSource);
41     }
42 
43 }

 1 @Configuration
 2 @PropertySource("classpath:datasource.properties")
 3 @MapperScan(basePackages = "org.allen.demo.dao.dbTwo", sqlSessionTemplateRef = "sqlSessionTemplate2")
 4 public class DataSource2Config {
 5 
 6     @Autowired
 7     private Environment env;
 8 
 9     @Bean("dataSource2")
10     public DataSource dataSource(){
11         System.out.println("初始化数据源2开始。。。");
12         HikariDataSource ds = new HikariDataSource ();
13         ds.setDriverClassName(env.getProperty("spring.datasource.two.driver-class-name").trim());
14         ds.setJdbcUrl(env.getProperty("spring.datasource.two.url").trim());
15         ds.setUsername(env.getProperty("spring.datasource.two.username").trim());
16         ds.setPassword(env.getProperty("spring.datasource.two.password").trim());
17         System.out.println("初始化数据源2结束。。。");
18         return ds;
19     }
20 
21     @Bean("sqlSessionFactory2")
22     public SqlSessionFactory sqlSessionFactory(@Qualifier("dataSource2") DataSource dataSource2) throws Exception {
23         SqlSessionFactoryBean sfb = new SqlSessionFactoryBean();
24         sfb.setDataSource(dataSource2);
25         return sfb.getObject();
26     }
27 
28     @Bean("sqlSessionTemplate2")
29     public SqlSessionTemplate sqlSessionTemplate(@Qualifier("sqlSessionFactory2") SqlSessionFactory sqlSessionFactory2){
30         SqlSessionTemplate sft = new SqlSessionTemplate(sqlSessionFactory2);
31         return sft;
32     }
33 
34     @Bean
35     public DataSourceTransactionManager transactionManager(@Qualifier("dataSource2") DataSource dataSource2){
36         return new DataSourceTransactionManager(dataSource2);
37     }
38 
39 }

注解@MapperScan的属性basePackages和sqlSessionTemplateRef将指定的dao层注入到指定的这个SqlSessionTemplate，这是接口和数据源绑定的最重要的一步

创建2个数据源对应的基础包下的接口

 1 @Mapper
 2 public interface CityOneMapper {
 3 
 4     @Insert("insert into t_city(cityCode, cityName) values(#{cityCode},#{cityName})")
 5     int insert(City city);
 6 
 7     @Delete("delete from t_city where id = #{id}")
 8     int delete(Integer id);
 9 
10     @Update("update t_city set cityName = #{cityName} where cityCode = #{cityCode}")
11     int update(City city);
12 
13     @Select("select * from t_city where id = #{id}")
14     City selectById(@Param("id") Integer id);
15 
16 }

 1 @Mapper
 2 public interface CityTwoMapper {
 3 
 4     @Insert("insert into t_city(cityCode, cityName) values(#{cityCode},#{cityName})")
 5     int insert(City city);
 6 
 7     @Delete("delete from t_city where id = #{id}")
 8     int delete(Integer id);
 9 
10     @Update("update t_city set cityName = #{cityName} where cityCode = #{cityCode}")
11     int update(City city);
12 
13     @Select("select * from t_city where id = #{id}")
14     City selectById(@Param("id") Integer id);
15 
16 }

分别创建2个service，实现接口方法

 1 @Service("cityOneService")
 2 public class CityOneService implements CityOneMapper {
 3 
 4     @Autowired
 5     private CityOneMapper cityOneMapper;
 6 
 7     @Override
 8     public int insert(City city) {
 9         return cityOneMapper.insert(city);
10     }
11 
12     @Override
13     public int delete(Integer id) {
14         return cityOneMapper.delete(id);
15     }
16 
17     @Override
18     public int update(City city) {
19         return cityOneMapper.update(city);
20     }
21 
22     @Override
23     public City selectById(Integer id) {
24         return cityOneMapper.selectById(id);
25     }
26 }

 1 @Service("cityService")
 2 public class CityTwoService implements CityTwoMapper {
 3 
 4     @Autowired
 5     private CityTwoMapper cityTwoMapper;
 6 
 7     @Override
 8     public int insert(City city) {
 9         return cityTwoMapper.insert(city);
10     }
11 
12     @Override
13     public int delete(Integer id) {
14         return cityTwoMapper.delete(id);
15     }
16 
17     @Override
18     public int update(City city) {
19         return cityTwoMapper.update(city);
20     }
21 
22     @Override
23     public City selectById(Integer id) {
24         return cityTwoMapper.selectById(id);
25     }
26 }

创建controller来测试

 1 @RestController
 2 public class DsTestController {
 3 
 4     @Autowired
 5     private CityOneService cityOneService;
 6 
 7     @Autowired
 8     private CityTwoService cityTwoService;
 9 
10     @GetMapping("/{id}")
11     public List<City> getCityById(@PathVariable("id") int id){
12         System.out.println("查询数据，id="+id);
13         List<City> cityList = new ArrayList<City>();
14         //查询数据库1的数据
15         City city1 = cityOneService.selectById(id);
16         cityList.add(city1);
17         //查询数据库2的数据
18         City city2 = cityTwoService.selectById(id);
19         cityList.add(city2);
20         return cityList;
21     }
22 
23 }

查看源码