java - 在 Spring Boot 中使用 EntityManager

Question

我想在 SpringBoot 中使用 EntityManager。

申请

@Configuration
@EnableRetry // To enable Spring retry
@EnableJpaRepositories
@EnableAspectJAutoProxy(proxyTargetClass=true)
@SpringBootApplication
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }

    @Bean
    public RestTemplate restTemplate() {
        return new RestTemplate();
    }    
}

邮件配置

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "mailEntityManager",
        transactionManagerRef = "mailTransactionManager",
        basePackageClasses = MmcMonitoringLog.class)

public class MailConfig {

    @Autowired(required = false)
    private PersistenceUnitManager persistenceUnitManager;

    @Bean
    @ConfigurationProperties("app.order.jpa")
    public JpaProperties orderJpaProperties() {
        return new JpaProperties();
    }

    @Bean
    @ConfigurationProperties(prefix = "app.order.datasource")
    public DataSource orderDataSource() {
        return (DataSource) DataSourceBuilder.create().type(DataSource.class).build();
    }

    @Bean
    public LocalContainerEntityManagerFactoryBean orderEntityManager(
            JpaProperties orderJpaProperties) {
        EntityManagerFactoryBuilder builder = createEntityManagerFactoryBuilder(orderJpaProperties);
        return builder
                .dataSource(orderDataSource())
                .packages(MmcMonitoringLog.class)
                .persistenceUnit("ordersDs")
                .build();
    }

    @Bean
    public JpaTransactionManager orderTransactionManager(EntityManagerFactory orderEntityManager) {
        return new JpaTransactionManager(orderEntityManager);
    }

    private EntityManagerFactoryBuilder createEntityManagerFactoryBuilder(JpaProperties customerJpaProperties) {
        JpaVendorAdapter jpaVendorAdapter = createJpaVendorAdapter(customerJpaProperties);
        return new EntityManagerFactoryBuilder(jpaVendorAdapter,
                customerJpaProperties.getProperties(), this.persistenceUnitManager);
    }

    private JpaVendorAdapter createJpaVendorAdapter(JpaProperties jpaProperties) {
        AbstractJpaVendorAdapter adapter = new HibernateJpaVendorAdapter();
        adapter.setShowSql(jpaProperties.isShowSql());
        adapter.setDatabase(jpaProperties.getDatabase());
        adapter.setDatabasePlatform(jpaProperties.getDatabasePlatform());
        adapter.setGenerateDdl(jpaProperties.isGenerateDdl());
        return adapter;
    }

}

邮件服务

public class MailService extends TaskAdaptor implements Runnable {

    @Autowired
    MmcMonitoringLogRepository mmcMonitoringLogRepository;

    @Override
    public void run() {

   List<MmcMonitoringLog> list = mmcMonitoringLogRepository.findByMonitoringLog("1");
   ......
}

应用程序属性

spring.datasource.url= jdbc:mysql://xxxx:3306/adb?autoReconnect=true&useSSL=false
spring.datasource.username=xxx
spring.datasource.password=xxx


# The SQL dialect makes Hibernate generate better SQL for the chosen database
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5Dialect

# Hibernate ddl auto (create, create-drop, update)
spring.jpa.hibernate.ddl-auto = none

我尝试执行以下 https://github.com/snicoll-demos/demo-multi-entity-managers/blob/master/src/main/java/demo/order/OrderConfig.java ，但我的 SpringBoot 立即停止，没有抛出任何异常。如果我删除 MailConfig，Springboot 可以启动。有什么问题 ？我走在正确的道路上吗？

Answer 1

我想你还没有设置数据源的值。您需要在 application.properties 中设置“app.order.jpa”和“app.order.datasource”属性才能使示例正常运行。

关于配置属性，您可以在这里阅读:

http://www.baeldung.com/configuration-properties-in-spring-boot

看这里的例子:

https://github.com/snicoll-demos/demo-multi-entity-managers/blob/master/src/main/resources/application.properties

app.customer.datasource.url=jdbc:h2:mem:customers;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE
app.customer.datasource.driver-class-name=org.h2.Driver
app.customer.jpa.properties.hibernate.hbm2ddl.auto=create

app.order.datasource.url=jdbc:h2:mem:orders;DB_CLOSE_DELAY=-1;DB_CLOSE_ON_EXIT=FALSE
app.order.datasource.driver-class-name=org.h2.Driver
app.order.jpa.properties.hibernate.hbm2ddl.auto=create