JPA多数据源配置

配置文件

方法1

spring:
  datasource:
    primary-method-1:
      driver-class-name: com.mysql.cj.jdbc.Driver
      url: jdbc:mysql://localhost:3306/database1
      username: root
      password: root
    other-method-1:
      driver-class-name: ...
      url: ...
      username: ...
      password: ...

方法2

spring:
  datasource:
    primary-method-2:
      driver-class-name: com.mysql.cj.jdbc.Driver
      jdbc-url: jdbc:mysql://localhost:3306/database1
      username: root
      password: root
      max-lifetime: ...
      ...
    other-method-2:
      driver-class-name: ...
      jdbc-url: ...
      username: ...
      password: ...
      ...

数据源配置

方法1

@Configuration
public class PrimaryDataSourceConfig {
    @Bean
    @Primary
    @ConfigurationProperties(prefix = "spring.datasource.primary-method-1")
    public DataSourceProperties primaryDataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean
    @Primary
    public DataSource primaryDataSource(
        @Qualifier("primaryDataSourceProperties") DataSourceProperties properties) {
        return properties.initializeDataSourceBuilder().build();
    }
}

@Configuration
public class OtherDataSourceConfig {
    @Bean
    @ConfigurationProperties(prefix = "spring.datasource.other-method-1")
    public DataSourceProperties otherDataSourceProperties() {
        return new DataSourceProperties();
    }

    @Bean
    public DataSource otherDataSource(
        @Qualifier("otherDataSourceProperties") DataSourceProperties properties) {
        return properties.initializeDataSourceBuilder().build();
    }
}

方法2

@Bean
@Primary
@ConfigurationProperties(prefix = "spring.datasource.primary-method-2")
public DataSource primaryDataSource() {
    return DataSourceBuilder.create().build();
}

@Bean
@ConfigurationProperties(prefix = "spring.datasource.other-method-2")
public DataSource otherDataSource() {
    return DataSourceBuilder.create().build();
}

• 若想要手动配置数据源并且对数据源的配置更有精确的控制，可以使用DataSourceBuilder.create().build()
• 若想要使用应用程序的配置（通常在 application.properties 或 application.yml 文件中配置）来配置数据源，可以使用 properties.initializeDataSourceBuilder().build()

JPA配置

@Configuration
@EnableJpaRepositories(
    entityManagerFactoryRef = "primaryEntityManagerFactory",
    transactionManagerRef = "primaryTransactionManager",
    basePackages = "cc.mousse.repository.primary")
@EnableTransactionManagement
public class PrimaryJpaConfig {
    @Resource JpaProperties jpaProperties;

    @Bean
    @Primary
    public LocalContainerEntityManagerFactoryBean primaryEntityManagerFactory(
        @Qualifier("primaryDataSource") DataSource dataSource, EntityManagerFactoryBuilder builder) {
        return builder
            .dataSource(dataSource)
            .properties(jpaProperties.getProperties())
            .packages("cc.mousse.entity.primary")
            .persistenceUnit("primaryPersistenceUnit")
            .build();
    }

    @Bean
    @Primary
    public EntityManager primaryEntityManager(
        @Qualifier("primaryEntityManagerFactory") EntityManagerFactory factory) {
        return factory.createEntityManager();
    }

    @Bean
    @Primary
    public PlatformTransactionManager primaryTransactionManager(
        @Qualifier("primaryEntityManagerFactory") EntityManagerFactory factory) {
        return new JpaTransactionManager(factory);
    }
}

@Configuration
@EnableJpaRepositories(
    entityManagerFactoryRef = "otherEntityManagerFactory",
    transactionManagerRef = "otherTransactionManager",
    basePackages = "cc.mousse.repository.other")
@EnableTransactionManagement
public class OtherJpaConfig {
    @Resource JpaProperties jpaProperties;

    @Bean
    public LocalContainerEntityManagerFactoryBean otherEntityManagerFactory(
        @Qualifier("otherDataSource") DataSource dataSource, EntityManagerFactoryBuilder builder) {
        return builder
            .dataSource(dataSource)
            .properties(jpaProperties.getProperties())
            .packages("cc.mousse.entity.other")
            .persistenceUnit("otherPersistenceUnit")
            .build();
    }

    @Bean
    public EntityManager otherEntityManager(
        @Qualifier("otherEntityManagerFactory") EntityManagerFactory factory) {
        return factory.createEntityManager();
    }

    @Bean
    public PlatformTransactionManager otherTransactionManager(
        @Qualifier("otherEntityManagerFactory") EntityManagerFactory factory) {
        return new JpaTransactionManager(factory);
    }
}

问题

无法自动装配。找不到 'xxx' 类型的 Bean。

• @SpringBootApplication默认扫描范围是启动类所在的包及其子包
• 要扫描本包以外的包，需要添加@SpringBootApplication(scanBasePackages = "cc.mousse")