Spring boot - how to configure multiple datasources

Question

I am trying to setup multiple data sources(MySql, Postgres & Oracle) using Spring boot. I am not using JPA. Setting up with a JdbcTemplate.

I have tried setting

Answer 1

Here is complete solution to your problem ...

Your configuration classes will look like this :

MySqlConfiguration.java

@Configuration
public class MySqlConfiguration {

   @Bean(name = "dMySql")
   @ConfigurationProperties(prefix = "spring.datasource.d.int-mysql")
   public DataSource mysqlDrupalDataSource() {
     return DataSourceBuilder.create().build();
   }

   @Bean(name = "dJdbc")
   public JdbcTemplate drupalJdbcTemplate(@Qualifier("dMySql") DataSource dMySql) {
      return new JdbcTemplate(dMySql);
   }

   @Bean(name = "mMySql")
   @ConfigurationProperties(prefix = "spring.datasource.m.int-mysql")
   public DataSource mysqlDrupalDataSource() {
      return DataSourceBuilder.create().build();
   }

   @Bean(name = "mJdbc")
   public JdbcTemplate drupalJdbcTemplate(@Qualifier("mMySql") DataSource mMySql) {
      return new JdbcTemplate(mMySql);
   }
}

OracleConfiguration.java

@Configuration
public class OracleConfiguration {

   @Primary
   @Bean(name = "tOracle")
   @ConfigurationProperties(prefix = "spring.datasource.test-oracle")
   public DataSource heOracleDataSource() {
      return DataSourceBuilder.create().build();
   }

   @Bean(name = "tOracleJdbc")
   public JdbcTemplate jdbcTemplate(@Qualifier("tOracle") DataSource tOracle) {
      return new JdbcTemplate(tOracle);
   }

   @Bean(name = "iOracle")
   @ConfigurationProperties(prefix = "spring.datasource.int-oracle")
   public DataSource heOracleDataSource() {
      return DataSourceBuilder.create().build();
   }

   @Bean(name = "iOracleJdbc")
   public JdbcTemplate jdbcTemplate(@Qualifier("iOracle") DataSource iOracle) {
      return new JdbcTemplate(iOracle);
   }
}

and in your DAO class , you can autowire the JdbcTemplate like this :

@Repository
public class DAOImpl implements DAOInterface {

    @Autowired
    @Qualifier("dJdbc")
    private JdbcTemplate dJdbc;

    @Autowired
    @Qualifier("mJdbc")
    private JdbcTemplate mJdbc;

    @Autowired
    @Qualifier("tOracleJdbc")
    private JdbcTemplate tOracleJdbc;

    @Autowired
    @Qualifier("iOracleJdbc")
    private JdbcTemplate iOracleJdbc;

    @Override
    public Map getBasicStudentInfo(String MAIL) {
        return dJdbc.queryForMap(GET_BASIC_STUDENT_INFO, new Object[]{MAIL});
    }

    .
    .
    .
}

Note: Make Sure to annotate one of DataSource with @Primary annotation