springcloud+hibernate+JPA+EntityManager Oracle 双数据源配置_java中yml配置hibernate多数据源调用接口

一个需求需要在服务里增加一个新的数据源,框架也有点奇葩查了一些资料终于研究好了!供大家借鉴!!!

1. yml配置多个数据源(树形排列也可以)

   spring.datasource.primary.url=jdbc:oracle:thin:@//dev-ceshi:1521/d0prps
   spring.datasource.primary.username=123123
   spring.datasource.primary.password=123456
    
   spring.datasource.secondary.url=jdbc:oracle:thin:@//sit-ceshi:1521/t0prps
   spring.datasource.secondary.username=123456
   spring.datasource.secondary.password=123456
   

2. 创建数据源配置类注意几个注解

   1. @Configuration:
      被注解的类内部包含有一个或多个被@Bean注解的方法，这些方法将会被AnnotationConfigApplicationContext或AnnotationConfigWebApplicationContext类进行扫描，并用于构建bean定义，初始化Spring容器。
      一句话解释就是用上这注解,系统启动是就会自动注入到容器中

   2.  @Primary：自动装配时当出现多个Bean候选者时，被注解为@Primary的Bean将作为首选者，否则将抛出异常

3. 创建数据源类

   import org.springframework.beans.factory.annotation.Qualifier;
   import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
   import org.springframework.boot.context.properties.ConfigurationProperties;
   import org.springframework.context.annotation.Bean;
   import org.springframework.context.annotation.Configuration;
   import org.springframework.context.annotation.Primary;
    
   import javax.sql.DataSource;
    
   /**
    * @NAME: 
    * @DATE: 2021/9/22
    * 双数据源配置
    **/
   @Configuration
   public class DataSourcesConfig {
       @Bean(name = "primaryDataSource")
       @Qualifier("primaryDataSource")
       @Primary//自动装配 就是默认使用此数据源
       @ConfigurationProperties(prefix="spring.datasource.primary")
       public DataSource primaryDataSource() {
           System.out.println("primary db built");
           return DataSourceBuilder.create().build();
       }
    
       @Bean(name = "secondaryDataSource")
       @Qualifier("secondaryDataSource")
       @ConfigurationProperties(prefix="spring.datasource.secondary")
       public DataSource secondaryDataSource() {
           System.out.println("secondary db built");
           return DataSourceBuilder.create().build();
       }
   }
   

   创建secondary数据源单独配置

   import org.springframework.beans.factory.annotation.Autowired;
   import org.springframework.beans.factory.annotation.Qualifier;
   import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
   import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
   import org.springframework.context.annotation.Bean;
   import org.springframework.context.annotation.Configuration;
   import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
   import org.springframework.orm.jpa.JpaTransactionManager;
   import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
   import org.springframework.transaction.PlatformTransactionManager;
   import org.springframework.transaction.annotation.EnableTransactionManagement;
    
   import javax.persistence.EntityManager;
   import javax.sql.DataSource;
   import java.util.Map;
    
    
   /**
    * @NAME:
    * @DATE: 2021/9/22
    **/
   @Configuration
   @EnableTransactionManagement//事务管理注解
   @EnableJpaRepositories(
           entityManagerFactoryRef = "entityManagerFactorySecondary",
           transactionManagerRef = "transactionManagerSecondary",
           basePackages = {"com.fulan.trade.nbzdata.repository"})
   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.fulan.trade.nbzdata.entity") //设置实体类所在位置
                   .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());
       }
   }
   

   创建primary数据源单独配置

   import org.springframework.beans.factory.annotation.Autowired;
   import org.springframework.beans.factory.annotation.Qualifier;
   import org.springframework.boot.autoconfigure.orm.jpa.JpaProperties;
   import org.springframework.boot.orm.jpa.EntityManagerFactoryBuilder;
   import org.springframework.context.annotation.Bean;
   import org.springframework.context.annotation.Configuration;
   import org.springframework.context.annotation.Primary;
   import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
   import org.springframework.orm.jpa.JpaTransactionManager;
   import org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean;
   import org.springframework.transaction.PlatformTransactionManager;
   import org.springframework.transaction.annotation.EnableTransactionManagement;
    
   import javax.persistence.EntityManager;
   import javax.sql.DataSource;
   import java.util.Map;
    
   /**
    * @NAME: hzan
    * @DATE: 2021/9/22
    **/
   @Configuration
   @EnableTransactionManagement
   @EnableJpaRepositories(
           entityManagerFactoryRef="entityManagerFactoryPrimary",
           transactionManagerRef="transactionManagerPrimary",
           basePackages= { "com.fulan.trade.repository" }) //设置Repository所在位置可以设置多个
   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.fulan.trade.entity") //设置实体类所在位置
                   .persistenceUnit("primaryPersistenceUnit")
                   .build();
       }
    
       @Autowired(required=false)
       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());
       }
    
   }
   

   按照上面配置的repository位置创建接口就可以实现JPA的查询了

4. hibernate+EntityManager使用

   当你使用EntityManager 时

   正常引用是 会默认上述自动装载的数据源

   @Autowired
   @PersistenceContext
   private EntityManager entityManager;

   可以通过

   @PersistenceContext 中的 unitName 属性进行设置 

   @Autowired
   @PersistenceContext(unitName="entityManagerFactorySecondary")
   private EntityManager entityManager;

   这样配置就可以自定数据源了