Multiple database with Spring+Hibernate+JPA

Question

I'm trying to configure Spring+Hibernate+JPA for work with two databases (MySQL and MSSQL)

my datasource-context.xml:

xml version="1.0" encoding="UTF-8"?>
 xmlns="http://www.springframework.org/schema/beans"
 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop"
 xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
  http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
  http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
  http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-2.5.xsd"
 xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx"
 xmlns:util="http://www.springframework.org/schema/util">

 
  id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
  destroy-method="close" p:driverClassName="${local.jdbc.driver}" p:url="${local.jdbc.url}"
  p:username="${local.jdbc.username}" p:password="${local.jdbc.password}">
 

  id="dataSourceRemote" class="org.apache.commons.dbcp.BasicDataSource"
  destroy-method="close" p:driverClassName="${remote.jdbc.driver}"
  p:url="${remote.jdbc.url}" p:username="${remote.jdbc.username}"
  p:password="${remote.jdbc.password}" />

  id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager"
  p:entity-manager-factory-ref="entityManagerFactory" />

 
  transaction-manager="transactionManager" />

  id="persistenceUnitManager"
  class="org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager">
         name="persistenceXmlLocations">
    value-type="java.lang.String">
    classpath*:config/persistence.local.xml

score 11 · Answer 1

You need to use persistenceXmlLocations property (note the plural) rather thanpersistenceXmlLocation. It's a string array, so it'll be auto-converted from list:

 id="persistenceUnitManager"
      class="org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager">
   name="persistenceXmlLocations">
    classpath*:config/persistence.local.xml

sth · Answer 2 · 2010-06-07 19:55:12Z

Justin, number 3 can be done in a more standard way like this:

In your Spring context:
```
 />
```

In your Spring-managed DAOs (note the unitName property):

@PersistenceContext(unitName = "pu1"`) protected EntityManager entityManager;

This way a properly intantiated EntityManager corresponding to the persistence unit named "pu1" would be injected in the corresponding DAOs.

I don't believe that Spring supports the unitName attribute prior to version 3, FYI. — Lyle, Jan 31 '11 at 21:00

Byron Q · Answer 3 · 2013-01-20 11:04:01Z

If you follow this tutorial, http://www.javacodegeeks.com/2010/05/jboss-42x-spring-3-jpa-hibernate.htmlyou can make the following changes to access two different databases:

persistence.xml, define a second pesristence-unit for your second database.
spring.xml, define a second entityManagerFactory bean under a different name, lets say "entityManagerFactoryDB2" and configure it to use the persistent unit for the second database.

for every DAO you want to access the second database include the following :

@Autowired
private EntityManagerFactory entityManagerFactoryDB2;

@PostConstruct
public void init() {
    super.setEntityManagerFactory(entityManagerFactoryDB2);
}

Thats all!

On spring service classes, use the DAOs as usual!

Kumar's Blog

Tuesday, December 31, 2013

Multiple database with Spring+Hibernate+JPA

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