Spring-data-jpa support

The configuration of the data source can follow the implementation of DataSourceConfig in the above example.

Add a new JPA configuration for the first data source. Note the two annotations used to specify the location of the Entity entity and Repository corresponding to the data source. @Primary Distinguish master data sources.

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactoryPrimary",
        transactionManagerRef="transactionManagerPrimary",
        basePackages= { "com.didispace.domain.p" }) //Set Repository Location
public class PrimaryConfig {

    @Autowired @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;

    @Primary
    @Bean(name = "entityManagerPrimary")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
    }

    @Primary
    @Bean(name = "entityManagerFactoryPrimary")
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary (EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(primaryDataSource)
                .properties(getVendorProperties(primaryDataSource))
                .packages("com.didispace.domain.p") //Set the location of the entity class
                .persistenceUnit("primaryPersistenceUnit")
                .build();
    }

    @Autowired
    private JpaProperties jpaProperties;

    private Map<String, String> getVendorProperties(DataSource dataSource) {
        return jpaProperties.getHibernateProperties(dataSource);
    }

    @Primary
    @Bean(name = "transactionManagerPrimary")
    public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
    }

}

A new JPA configuration for the second data source is added, which is similar to the first data source, as follows:

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactorySecondary",
        transactionManagerRef="transactionManagerSecondary",
        basePackages= { "com.didispace.domain.s" }) //Set Repository Location
public class SecondaryConfig {

    @Autowired @Qualifier("secondaryDataSource")
    private DataSource secondaryDataSource;

    @Bean(name = "entityManagerSecondary")
    public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
        return entityManagerFactorySecondary(builder).getObject().createEntityManager();
    }

    @Bean(name = "entityManagerFactorySecondary")
    public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary (EntityManagerFactoryBuilder builder) {
        return builder
                .dataSource(secondaryDataSource)
                .properties(getVendorProperties(secondaryDataSource))
                .packages("com.didispace.domain.s") //Set the location of the entity class
                .persistenceUnit("secondaryPersistenceUnit")
                .build();
    }

    @Autowired
    private JpaProperties jpaProperties;

    private Map<String, String> getVendorProperties(DataSource dataSource) {
        return jpaProperties.getHibernateProperties(dataSource);
    }

    @Bean(name = "transactionManagerSecondary")
    PlatformTransactionManager transactionManagerSecondary(EntityManagerFactoryBuilder builder) {
        return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
    }

}

After completing the above configuration, the main data source entity and data access object are located at: com.didispace.domain.p, and the number of data sources entity and data access interface are located at: com.didispace.domain.s.

Create respective entity and data access interfaces under these two package s

• Create User entities and corresponding Repository interfaces under the master data source

  @Entity
  public class User {
  
      @Id
      @GeneratedValue
      private Long id;
  
      @Column(nullable = false)
      private String name;
  
      @Column(nullable = false)
      private Integer age;
  
      public User(){}
  
      public User(String name, Integer age) {
          this.name = name;
          this.age = age;
      }
  
      // Omit getter, setter
  
  }

  public interface UserRepository extends JpaRepository<User, Long> {
  
  }

   

• Create Message Entities and Corresponding Repository Interfaces from Data Sources

  @Entity
  public class Message {
  
      @Id
      @GeneratedValue
      private Long id;
  
      @Column(nullable = false)
      private String name;
  
      @Column(nullable = false)
      private String content;
  
      public Message(){}
  
      public Message(String name, String content) {
          this.name = name;
          this.content = content;
      }
  
      // Omit getter, setter
  
  }

  public interface MessageRepository extends JpaRepository<Message, Long> {
  
  }

  Next, test cases are used to verify the use of these two configurations for different data sources for data manipulation.

  @RunWith(SpringJUnit4ClassRunner.class)
  @SpringApplicationConfiguration(Application.class)
  public class ApplicationTests {
  
  	@Autowired
  	private UserRepository userRepository;
  	@Autowired
  	private MessageRepository messageRepository;
  
  	@Test
  	public void test() throws Exception {
  
  		userRepository.save(new User("aaa", 10));
  		userRepository.save(new User("bbb", 20));
  		userRepository.save(new User("ccc", 30));
  		userRepository.save(new User("ddd", 40));
  		userRepository.save(new User("eee", 50));
  
  		Assert.assertEquals(5, userRepository.findAll().size());
  
  		messageRepository.save(new Message("o1", "aaaaaaaaaa"));
  		messageRepository.save(new Message("o2", "bbbbbbbbbb"));
  		messageRepository.save(new Message("o3", "cccccccccc"));
  
  		Assert.assertEquals(3, messageRepository.findAll().size());
  
  	}
  
  }
  

  Source of source code