jpa配置多数据源教程很多，在Springboot2之后有一些变化，来看一下。
application.yml如下
spring:
application:
name: t3cc
datasource:
primary:
jdbc-url: jdbc:mysql://${MYSQL_HOST:localhost}:${MYSQL_PORT:3306}/${DB_NAME:anbang}?useUnicode=true&characterEncoding=UTF8&serverTimezone=Hongkong
username: root
password: root
secondary:
jdbc-url: jdbc:mysql://${MYSQL_HOST:localhost}:${MYSQL_PORT:3306}/${DB_NAME:anbang1}?useUnicode=true&characterEncoding=UTF8&serverTimezone=Hongkong
username: root
password: root
jpa:
database: mysql
database-platform: org.hibernate.dialect.MySQL5InnoDBDialect #不加这句则默认为myisam引擎
hibernate:
ddl-auto: update
naming:
physical-strategy: org.springframework.boot.orm.jpa.hibernate.SpringPhysicalNamingStrategy
open-in-view: true
properties:
enable_lazy_load_no_trans: true
show-sql: true
cloud:
nacos:
discovery:
server-addr: ${NACOS_SERVER:localhost:8848}
###############################---log---##############################
logging:
file: ./logback.logyml里配置了两个数据源，和一些jpa和Hibernate的配置。
下面是DataSource的配置
@Configuration
public class DataSourceConfig {
@Primary
@Bean(name = "primaryDataSource")
@ConfigurationProperties(prefix = "spring.datasource.primary")
public DataSource dataSourceOrder() {
return DataSourceBuilder.create().build();
}
@Bean(name = "secondaryDataSource")
@ConfigurationProperties(prefix = "spring.datasource.secondary")
public DataSource dataSourceAuth() {
return DataSourceBuilder.create().build();
}
}下面是第一个数据源的配置
package com.mm.dmp.t3cc.config;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateProperties;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
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.annotation.Resource;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
entityManagerFactoryRef = "entityManagerFactoryPrimary",
transactionManagerRef = "transactionManagerPrimary",
basePackages = {"com.mm.dmp.t3cc.core.repository.one"})
public class OneConfig {
@Resource
@Qualifier("primaryDataSource")
private DataSource primaryDataSource;
@Primary
@Bean(name = "entityManagerPrimary")
public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
return entityManagerFactoryPrimary(builder).getObject().createEntityManager();
}
@Resource
private JpaProperties jpaProperties;
@Resource
private HibernateProperties properties;
@Primary
@Bean(name = "entityManagerFactoryPrimary")
public LocalContainerEntityManagerFactoryBean entityManagerFactoryPrimary(EntityManagerFactoryBuilder builder) {
LocalContainerEntityManagerFactoryBean entityManagerFactory = builder
.dataSource(primaryDataSource)
//.packages(classes)
//设置实体类所在位置
.packages("com.mm.dmp.t3cc.core.entity.one")
.persistenceUnit("primaryPersistenceUnit")
//.properties(jpaProperties.getProperties())
.properties(properties.determineHibernateProperties(jpaProperties.getProperties(), new HibernateSettings()))
.build();
return entityManagerFactory;
}
@Primary
@Bean(name = "transactionManagerPrimary")
public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
return new JpaTransactionManager(entityManagerFactoryPrimary(builder).getObject());
}
}这里会和别人的配置不一样，主要区别在于HibernateProperties。别人的在第61行，我注释掉的那行，会直接使用jpaProperties.getProperties()。当你这样写之后，会发现yml里配置的Hibernate的update自动生成表，和命名方式并没有生效。
原因我们可以看一下。
这里就是jpaProperties.getProperties()的地方，如果打断点可以看到，只有箭头这一个配置被加载进去了。上面的Hibernate的ddl和naming并没有进去。
来看一下HibernateProperties
这里才是真正让自动建表生效的地方，然而并没有加载进去。那么就需要我们手工来添加了。
这里面有个determineHibernateProperties方法，就是来组合jpaProperties和HibernateProperties的地方。我们应该使用这个方法来组合整个配置的map对象。
也就是在OneConfig类中，把两个Properties都定义出来，然后组合一下，就是箭头的地方。在debug时，就可以看到Hibernate的配置也都加载进来了。
OK，以上就是动态数据源配置Hibernate自动建表不生效的原因。
下面是第二个数据源的配置
package com.mm.dmp.t3cc.config;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateProperties;
import org.springframework.boot.autoconfigure.orm.jpa.HibernateSettings;
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.annotation.Resource;
import javax.persistence.EntityManager;
import javax.sql.DataSource;
@Configuration
@EnableTransactionManagement
@EnableJpaRepositories(
entityManagerFactoryRef = "entityManagerFactorySecondary",
transactionManagerRef = "transactionManagerSecondary",
basePackages = {"com.mm.dmp.t3cc.core.repository.two"}) //设置Repository所在位置
public class TwoConfig {
@Resource
@Qualifier("secondaryDataSource")
private DataSource secondaryDataSource;
@Resource
private JpaProperties jpaProperties;
@Resource
private HibernateProperties properties;
@Bean(name = "entityManagerSecondary")
public EntityManager entityManager(EntityManagerFactoryBuilder builder) {
return entityManagerFactorySecondary(builder).getObject().createEntityManager();
}
@Bean(name = "entityManagerFactorySecondary")
public LocalContainerEntityManagerFactoryBean entityManagerFactorySecondary(EntityManagerFactoryBuilder builder) {
LocalContainerEntityManagerFactoryBean entityManagerFactory
= builder
.dataSource(secondaryDataSource)
//.packages(classes)
//设置实体类所在位置
.packages("com.mm.dmp.t3cc.core.entity.two")
.persistenceUnit("secondaryPersistenceUnit")
.properties(properties.determineHibernateProperties(jpaProperties.getProperties(), new
HibernateSettings()))
.build();
return entityManagerFactory;
}
@Bean(name = "transactionManagerSecondary")
public PlatformTransactionManager transactionManagerPrimary(EntityManagerFactoryBuilder builder) {
return new JpaTransactionManager(entityManagerFactorySecondary(builder).getObject());
}
}如果你觉得这样比较麻烦，并且还有分库分表的需求，那么可以使用sharding jdbc来操作，移步这一篇文章
以上为个人经验，希望能给大家一个参考，也希望大家多多支持编程网。
