Question

我正在尝试使用Spring Boot和Spring Data JPA将每个@Repositories连接到不同的DataSource。我使用以下http://xantorohara.blogspot.com/2013/11/spring-boot-jdbc-with-multiple.html作为参考。以下是我尝试使用Spring Data JPA实现类似解决方案的代码。

CustomerDbConfig.java （第一个数据源连接）

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "orderEntityManager",
        transactionManagerRef = "orderTransactionManager",
        basePackages = {"com.mm.repository.customer"})
public class CustomerDbConfig {

    @Bean(name = "customerEntityManager")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(){
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(dataSource());
        em.setPackagesToScan(new String[] {"com.mm.domain.customer"});

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(additionalJpaProperties());
        em.setPersistenceUnitName("customerPersistence");
        em.setPackagesToScan("com.mm.domain.customer");

        return em;
    }

    Properties additionalJpaProperties(){
        Properties properties = new Properties();
        properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");
        properties.setProperty("hibernate.show_sql", "true");

        return properties;
    }

    @Bean
    public DataSource dataSource(){
        return DataSourceBuilder.create()
                .url("jdbc:h2:mem:customer:H2")
                .driverClassName("org.h2.Driver")
                .username("sa")
                .password("")
                .build();
    }   

    @Bean(name = "customerTransactionManager")
    public PlatformTransactionManager transactionManager(EntityManagerFactory emf){
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);

        return transactionManager;
    }
}

CustomerDbConfig.java （第二个数据源）

@Configuration
@EnableJpaRepositories(
        entityManagerFactoryRef = "orderEntityManager",
        transactionManagerRef = "orderTransactionManager",
        basePackages = {"com.mm.repository.customer"})
public class CustomerDbConfig {

    @Bean(name = "customerEntityManager")
    public LocalContainerEntityManagerFactoryBean entityManagerFactory(){
        LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
        em.setDataSource(dataSource());
        em.setPackagesToScan(new String[] {"com.mm.domain.customer"});

        JpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
        em.setJpaVendorAdapter(vendorAdapter);
        em.setJpaProperties(additionalJpaProperties());
        em.setPersistenceUnitName("customerPersistence");
        em.setPackagesToScan("com.mm.domain.customer");

        return em;
    }

    Properties additionalJpaProperties(){
        Properties properties = new Properties();
        properties.setProperty("hibernate.hbm2ddl.auto", "create-drop");
        properties.setProperty("hibernate.dialect", "org.hibernate.dialect.H2Dialect");
        properties.setProperty("hibernate.show_sql", "true");

        return properties;
    }

    @Bean
    public DataSource dataSource(){
        return DataSourceBuilder.create()
                .url("jdbc:h2:mem:customer:H2")
                .driverClassName("org.h2.Driver")
                .username("sa")
                .password("")
                .build();
    }   

    @Bean(name = "customerTransactionManager")
    public PlatformTransactionManager transactionManager(EntityManagerFactory emf){
        JpaTransactionManager transactionManager = new JpaTransactionManager();
        transactionManager.setEntityManagerFactory(emf);

        return transactionManager;
    }
}

Customer.java （型号）

@Entity
@Table(name = "customer")
@Data
@EqualsAndHashCode(exclude = {"id"})
public class Customer {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @Column(name = "name", nullable = false)
    private String name;

    @Column(name = "age", nullable = false)
    private Integer age;

....

Order.java （型号）

@Entity
@Table(name = "order")
@Data
@EqualsAndHashCode(exclude = {"id"})
public class Order {

    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Integer id;

    @Column(name = "code", nullable = false)
    private Integer code;

    @Column(name = "quality", nullable = false)
    private Integer quality;

...

CustomerRepository.java

public interface CustomerRepository extends JpaRepository<Customer, Integer>{

}

OrderRepository.java

public interface OrderRepository extends JpaRepository<Order, Integer> {

}

最后， Application.java

@Configuration
@ComponentScan
@EnableAutoConfiguration
public class Application extends SpringApplication{

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

        @Bean
        public ServletRegistrationBean h2Console() {
            ServletRegistrationBean reg = new ServletRegistrationBean(new WebServlet(), "/console/*");
            reg.setLoadOnStartup(1);
            return reg;
        }
}

在开始时，会抛出以下例外：

-10-10 15:45:24.757 ERROR 1549 --- [           main] o.s.boot.SpringApplication               : Application startup failed

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'customerTransactionManager' defined in class path resource [com/mm/boot/multidb/CustomerConfig.class]: Unsatisfied dependency expressed through constructor argument with index 0 of type [javax.persistence.EntityManagerFactory]: : No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:747)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:462)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1095)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:990)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:762)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:109)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:952)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:941)
    at com.mm.boot.multidb.Application.main(Application.java:17)
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:974)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:862)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:811)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:739)
    ... 18 common frames omitted

Exception in thread "main" org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'customerTransactionManager' defined in class path resource [com/mm/boot/multidb/CustomerConfig.class]: Unsatisfied dependency expressed through constructor argument with index 0 of type [javax.persistence.EntityManagerFactory]: : No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager; nested exception is org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:747)
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:462)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1095)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:990)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:504)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:706)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:762)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:109)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:320)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:952)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:941)
    at com.mm.boot.multidb.Application.main(Application.java:17)
Caused by: org.springframework.beans.factory.NoUniqueBeanDefinitionException: No qualifying bean of type [javax.persistence.EntityManagerFactory] is defined: expected single matching bean but found 2: customerEntityManager,orderEntityManager
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:974)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:862)
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:811)
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:739)
    ... 18 more

可以在GitHub（https://github.com/tonym2105/samples/tree/master/boot-multidb-sample）

上找到该示例的完整代码

提前感谢您的帮助。

Answer 1

使用@EnableAutoConfiguration和application.properties可以有另一种方法来拥有多个dataSource。

基本上在application.properties上放置多个dataSource配置信息，并通过@EnableAutoConfiguration自动为第一个dataSource生成默认设置（dataSource和entityManagerFactory）。但对于下一个dataSource，请通过属性文件中的信息手动创建dataSource，entityManagerFactory和transactionManager。

下面是我设置两个dataSource的示例。第一个dataSource由@EnableAutoConfiguration设置，只能为一个配置而不是多个配置。这将产生＆＃39; transactionManager＆＃39;通过 DataSourceTransactionManager ，它看起来是由注释生成的默认事务管理器。但是，我已经看到事务没有从预定的线程池中开始出现问题，仅针对默认的DataSourceTransactionManager以及有多个事务管理器时。所以我也通过 JpaTransactionManager 为第一个数据源手动创建了事务管理器，并分配了＆＃39; transactionManager＆＃39; bean名称和默认的entityManagerFactory。第一个dataSource的JpaTransactionManager肯定会解决来自ScheduledThreadPool的线程上的奇怪事务问题。

更新Spring Boot 1.3.0.RELEASE

我发现我之前使用@EnableAutoConfiguration配置的默认dataSource在查找带有Spring Boot 1.3版本的entityManagerFactory时遇到了问题。在我介绍自己的transactionManager之后，可能默认的entityManagerFactory不是由@EnableAutoConfiguration生成的。所以现在我自己创建entityManagerFactory。所以我不需要使用@EntityScan。所以看起来我越来越多地通过@EnableAutoConfiguration来完成设置。

在没有@EnableAutoConfiguration的情况下设置第二个dataSource并创建另一个事务管理器＆＃39;通过手动方式。

由于从PlatformTransactionManager扩展了多个transactionManager，我们应该指定在每个@Transactional注释上使用哪个transactionManager

默认存储库配置

@Configuration
@EnableTransactionManagement
@EnableAutoConfiguration
@EnableJpaRepositories(
        entityManagerFactoryRef = "entityManagerFactory",
        transactionManagerRef = "transactionManager",
        basePackages = {"com.mysource.repository"})
public class RepositoryConfig {
    @Autowired
    JpaVendorAdapter jpaVendorAdapter;

    @Autowired
    DataSource dataSource;

    @Bean(name = "entityManager")
    public EntityManager entityManager() {
        return entityManagerFactory().createEntityManager();
    }

    @Primary
    @Bean(name = "entityManagerFactory")
    public EntityManagerFactory entityManagerFactory() {
        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource(dataSource);
        emf.setJpaVendorAdapter(jpaVendorAdapter);
        emf.setPackagesToScan("com.mysource.model");
        emf.setPersistenceUnitName("default");   // <- giving 'default' as name
        emf.afterPropertiesSet();
        return emf.getObject();
    }

    @Bean(name = "transactionManager")
    public PlatformTransactionManager transactionManager() {
        JpaTransactionManager tm = new JpaTransactionManager();
        tm.setEntityManagerFactory(entityManagerFactory());
        return tm;
    }
}

另一个存储库配置

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
        entityManagerFactoryRef = "anotherEntityManagerFactory",
        transactionManagerRef = "anotherTransactionManager",
        basePackages = {"com.mysource.anothersource.repository"})
public class AnotherRepositoryConfig {
    @Autowired
    JpaVendorAdapter jpaVendorAdapter;

    @Value("${another.datasource.url}")
    private String databaseUrl;

    @Value("${another.datasource.username}")
    private String username;

    @Value("${another.datasource.password}")
    private String password;

    @Value("${another.dataource.driverClassName}")
    private String driverClassName;

    @Value("${another.datasource.hibernate.dialect}")
    private String dialect;

    public DataSource dataSource() {
        DriverManagerDataSource dataSource = new DriverManagerDataSource(databaseUrl, username, password);
        dataSource.setDriverClassName(driverClassName);
        return dataSource;
    }

    @Bean(name = "anotherEntityManager")
    public EntityManager entityManager() {
        return entityManagerFactory().createEntityManager();
    }

    @Bean(name = "anotherEntityManagerFactory")
    public EntityManagerFactory entityManagerFactory() {
        Properties properties = new Properties();
        properties.setProperty("hibernate.dialect", dialect);

        LocalContainerEntityManagerFactoryBean emf = new LocalContainerEntityManagerFactoryBean();
        emf.setDataSource(dataSource());
        emf.setJpaVendorAdapter(jpaVendorAdapter);
        emf.setPackagesToScan("com.mysource.anothersource.model");   // <- package for entities
        emf.setPersistenceUnitName("anotherPersistenceUnit");
        emf.setJpaProperties(properties);
        emf.afterPropertiesSet();
        return emf.getObject();
    }

    @Bean(name = "anotherTransactionManager")
    public PlatformTransactionManager transactionManager() {
        return new JpaTransactionManager(entityManagerFactory());
    }
}

<强> application.properties

# database configuration
spring.datasource.url=jdbc:h2:file:~/main-source;AUTO_SERVER=TRUE
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.driver-class-name=org.h2.Driver
spring.datasource.continueOnError=true
spring.datasource.initialize=false

# another database configuration
another.datasource.url=jdbc:sqlserver://localhost:1433;DatabaseName=another;
another.datasource.username=username
another.datasource.password=
another.datasource.hibernate.dialect=org.hibernate.dialect.SQLServer2008Dialect 
another.datasource.driverClassName=com.microsoft.sqlserver.jdbc.SQLServerDriver

为@Transactional注释选择合适的transactionManager

第一个数据源的服务

@Service("mainService")
@Transactional("transactionManager")
public class DefaultDataSourceServiceImpl implements DefaultDataSourceService       
{

   //

}

为其他数据源提供服务

@Service("anotherService")
@Transactional("anotherTransactionManager")
public class AnotherDataSourceServiceImpl implements AnotherDataSourceService 
{

   //

}

Answer 2

这是我的解决方案。基于spring-boot.1.2.5.RELEASE。

application.properties

first.datasource.driver-class-name=com.mysql.jdbc.Driver
first.datasource.url=jdbc:mysql://127.0.0.1:3306/test
first.datasource.username=
first.datasource.password=
first.datasource.validation-query=select 1

second.datasource.driver-class-name=com.mysql.jdbc.Driver
second.datasource.url=jdbc:mysql://127.0.0.1:3306/test2
second.datasource.username=
second.datasource.password=
second.datasource.validation-query=select 1

DataSourceConfig.java

@Configuration
public class DataSourceConfig {
    @Bean
    @Primary
    @ConfigurationProperties(prefix="first.datasource")
    public DataSource firstDataSource() {
        DataSource ds =  DataSourceBuilder.create().build();
        return ds;
    }

    @Bean
    @ConfigurationProperties(prefix="second.datasource")
    public DataSource secondDataSource() {
        DataSource ds =  DataSourceBuilder.create().build();
        return ds;
    }
}

Answer 3

我检查了你在GitHub上提供的源代码。配置中存在多个错误/拼写错误。

在CustomerDbConfig / OrderDbConfig中，您应该引用customerEntityManager，包应该指向现有的包：

@Configuration
@EnableJpaRepositories(
    entityManagerFactoryRef = "customerEntityManager",
    transactionManagerRef = "customerTransactionManager",
    basePackages = {"com.mm.boot.multidb.repository.customer"})
public class CustomerDbConfig {

在customerEntityManager和orderEntityManager中扫描的包都没有指向正确的包：

em.setPackagesToScan("com.mm.boot.multidb.model.customer");

注入正确的EntityManagerFactory也不起作用。它应该是：

@Bean(name = "customerTransactionManager")
public PlatformTransactionManager transactionManager(EntityManagerFactory customerEntityManager){

}

以上是导致问题和例外。在@Bean方法中提供名称时，您确信可以注入适当的EMF。

我做的最后一件事是禁用自动配置JpaRepositories：

@EnableAutoConfiguration(exclude = JpaRepositoriesAutoConfiguration.class)

通过所有修复程序，应用程序可能会像您预期的那样启动！

Answer 4

感谢Steve Park和Rafal Borowiec的答案我得到了我的代码，但是，我有一个问题：DriverManagerDataSource是一个“简单”的实现，并且没有给你一个ConnectionPool （检查http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/jdbc/datasource/DriverManagerDataSource.html）。

因此，我替换了为DataSource返回secondDB的函数。

public DataSource <secondaryDB>DataSource() {
    // use DataSourceBuilder and NOT DriverManagerDataSource 
    // as this would NOT give you ConnectionPool
    DataSourceBuilder dataSourceBuilder = DataSourceBuilder.create();
    dataSourceBuilder.url(databaseUrl);
    dataSourceBuilder.username(username);
    dataSourceBuilder.password(password);
    dataSourceBuilder.driverClassName(driverClassName);
    return dataSourceBuilder.build();
}

此外，如果您不需要EntityManager，则可以删除entityManager()和@Bean注释。

另外，您可能希望删除配置类的basePackages注释：使用factoryBean.setPackagesToScan()调用维护它是足够的。

Answer 5

我在Spring Boot JPA Multiple Data Sources Example写了一篇完整的文章。在本文中，我们将学习如何在典型的Spring Boot Web应用程序中配置多个数据源并连接到多个数据库。我们将使用Spring Boot 2.0.5，JPA，Hibernate 5，Thymeleaf和H2数据库来构建一个简单的Spring Boot多个数据源Web应用程序。

Answer 6

不知道为什么，但它确实有效。两个配置相同，只需将xxx更改为您的名字。

@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
    entityManagerFactoryRef = "xxxEntityManager",
    transactionManagerRef = "xxxTransactionManager",
    basePackages = {"aaa.xxx"})
 public class RepositoryConfig {
@Autowired
private Environment env;

@Bean
@Primary
@ConfigurationProperties(prefix="datasource.xxx")
public DataSource xxxDataSource() {
    return DataSourceBuilder.create().build();
}

@Bean
public LocalContainerEntityManagerFactoryBean xxxEntityManager() {
    LocalContainerEntityManagerFactoryBean em = new LocalContainerEntityManagerFactoryBean();
    em.setDataSource(xxxDataSource());
    em.setPackagesToScan(new String[] {"aaa.xxx"});

    HibernateJpaVendorAdapter vendorAdapter = new HibernateJpaVendorAdapter();
    em.setJpaVendorAdapter(vendorAdapter);
    HashMap<String, Object> properties = new HashMap<String, Object>();
    properties.put("hibernate.show_sql", env.getProperty("hibernate.show_sql"));
    properties.put("hibernate.hbm2ddl.auto", env.getProperty("hibernate.hbm2ddl.auto"));
    properties.put("hibernate.dialect", env.getProperty("hibernate.dialect"));
    em.setJpaPropertyMap(properties);

    return em;
}

@Bean(name = "xxxTransactionManager")
public PlatformTransactionManager xxxTransactionManager() {
    JpaTransactionManager tm = new JpaTransactionManager();
    tm.setEntityManagerFactory(xxxEntityManager().getObject());
    return tm;
}

}

Spring Boot，Spring Data JPA，带有多个DataSources

6 个答案: