Spring-Data-Jpa的使用（2）--多数据源配置

在使用spring-data-jpa时，如果要配置多数据源，一般为以下三个步骤：

• 在配置文件配置多数据源
• 不同源的 repository 放入不同包路径
• 声明不同的包路径下使用不同的数据源、事务支持

1.配置文件配置多数据源

---

spring.primary.datasource.url=jdbc:mysql://localhost:3306/test
spring.primary.datasource.username=root
spring.primary.datasource.password=root
spring.primary.datasource.driver-class-name=com.mysql.jdbc.Driver

spring.secondary.datasource.url=jdbc:mysql://localhost:3306/test1
spring.secondary.datasource.username=root
spring.secondary.datasource.password=root
spring.secondary.datasource.driver-class-name=com.mysql.jdbc.Driver

2.不同源的 repository 放入不同包路径

---

3.声明不同的包路径下使用不同的数据源

---

将数据源注入到 Factory，配置 repository、domian 的位置，需要设置一个默认的数据源

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactoryPrimary",
        transactionManagerRef = "transactionManagerPrimary",
        basePackages = {"com.zb.boot.repository.primary"}//声明路径
)
public class PrimaryConfig {
    @Autowired
    private JpaProperties jpaProperties;
    @Autowired
    @Qualifier("primaryDataSource")
    private DataSource primaryDataSource;
    public EntityManager entityManager(EntityManagerFactoryBuilder builder){
        return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
    }
    @Bean(name = "entityManagerFactoryPrimary")
    @Primary
    public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder){
        return builder.dataSource(primaryDataSource)
                .properties(getVendorProperties(primaryDataSource))
                .packages("com.zb.boot.model")//实体类的路径
                .persistenceUnit("primaryPersistenceUnit")
                .build();
    }
    public Map<String, String> getVendorProperties(DataSource dataSource){
        return jpaProperties.getHibernateProperties(dataSource);
    }
    @Bean(name = "transactionManagerPrimary")
    @Primary
    PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder){
        return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
    }
}

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef="entityManagerFactorySecondary",
        transactionManagerRef="transactionManagerSecondary",
        basePackages= { "com.zb.boot.repository.secondary" })
public class SecondaryConfig {
    @Autowired
    private JpaProperties jpaProperties;

    @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.zb.boot.model")
                .persistenceUnit("secondaryPersistenceUnit")
                .build();
    }

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

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

}

读取两个配置源，构建两个数据源：

@Configuration
public class DataSourceConfig {

    @Bean(name = "primaryDataSource")
    @Qualifier("primaryDataSource")
    @ConfigurationProperties(prefix = "spring.primary.datasource")
    public DataSource primaryDataSource(){
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "secondaryDataSource")
    @Qualifier("secondaryDataSource")
    @Primary
    @ConfigurationProperties(prefix = "spring.secondary.datasource")
    public DataSource secondaryDataSource(){
        return DataSourceBuilder.create().build();
    }
}