Toplink and UUID

Question

If I persist a UUID using toplink that looks like 550e8400-e29b-41d4-a716-446655440000 in java, it is saved in som other format in the database. It starts with ACED....
What format is this? Is there some easy way in sql to convert between these formats? Why is it stored like this instead of 550e8400-e29b-41d4-a716-446655440000? Better indexing?
Thanks,
/Magnus

Answer 1

Could you please explain why this spring config from http://www.oracle.com/technology/products/ias/toplink/preview/how-to/toplink-jpa-spring.html :
<bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.OracleTopLinkJpaVendorAdapter">
<property name="showSql" value="true"/>
          <property name="databasePlatform" value="oracle.toplink.platform.database.oracle.OraclePlatform"/>
</bean>
</property>
          <property name="jpaProperties">
               <props>
                    <prop key="toplink.weaving">false</prop>
          <prop key="toplink.logging.level">FINEST</prop>
               </props>
          </property>
</bean>
Produces this output:
INFO: Building JPA container EntityManagerFactory for persistence unit 'em'
[TopLink Finest]: 2007.05.30 12:52:35.005--ServerSession(8303462)--Thread(Thread[main,5,main])--property=toplink.weaving; value=false
[TopLink Finest]: 2007.05.30 12:52:35.037--ServerSession(8303462)--Thread(Thread[main,5,main])--property=toplink.orm.throw.exceptions; default value=true
[TopLink Finer]: 2007.05.30 12:52:35.052--ServerSession(8303462)--Thread(Thread[main,5,main])--Searching for default mapping file in file:/C:/Documents%20and%20Settings/maghei/Skrivbord/HibernateFilterDemo/build/
[TopLink Config]: 2007.05.30 12:52:35.224--ServerSession(8303462)--Thread(Thread[main,5,main])--The alias name for the entity class [class se.lantmateriet.ormtest.domain.User] is being defaulted to: User.
[TopLink Config]: 2007.05.30 12:52:35.255--ServerSession(8303462)--Thread(Thread[main,5,main])--The column name for element [protected int se.lantmateriet.ormtest.domain.DomainEntity.id] is being defaulted to: ID.
[TopLink Config]: 2007.05.30 12:52:35.271--ServerSession(8303462)--Thread(Thread[main,5,main])--The column name for element [private java.util.UUID se.lantmateriet.ormtest.domain.DomainEntity.uuid] is being defaulted to: UUID.
[TopLink Config]: 2007.05.30 12:52:35.271--ServerSession(8303462)--Thread(Thread[main,5,main])--The column name for element [private java.lang.String se.lantmateriet.ormtest.domain.User.username] is being defaulted to: USERNAME.
[TopLink Config]: 2007.05.30 12:52:35.271--ServerSession(8303462)--Thread(Thread[main,5,main])--The column name for element [private boolean se.lantmateriet.ormtest.domain.User.activated] is being defaulted to: ACTIVATED.
[TopLink Finest]: 2007.05.30 12:52:35.271--ServerSession(8303462)--Thread(Thread[main,5,main])--property=toplink.weaving.changetracking; default value=false
[TopLink Finest]: 2007.05.30 12:52:35.271--ServerSession(8303462)--Thread(Thread[main,5,main])--property=toplink.weaving.lazy; default value=true
[TopLink Finest]: 2007.05.30 12:52:35.271--ServerSession(8303462)--Thread(Thread[main,5,main])--end predeploying Persistence Unit em; state Predeployed; factoryCount 1
And this config:
<bean id="emTest" class="se.lantmateriet.ormtest.persistence.em.TopLinkEntityManager" factory-method="getEntityManagerFactory">
</bean>
Where TopLinkEntityManager getEntityManagerFactory starts toplink like this:
EntityManagerFactoryProvider entityManagerFactoryProvider = new EntityManagerFactoryProvider();
     entityManagerFactory = entityManagerFactoryProvider.createEntityManagerFactory("em", new HashMap());
and creates this output:
[TopLink Finest]: 2007.05.30 12:52:35.365--ServerSession(14615608)--Thread(Thread[main,5,main])--property=toplink.weaving; value=false
[TopLink Finest]: 2007.05.30 12:52:35.365--ServerSession(14615608)--Thread(Thread[main,5,main])--property=toplink.orm.throw.exceptions; default value=true
[TopLink Finer]: 2007.05.30 12:52:35.365--ServerSession(14615608)--Thread(Thread[main,5,main])--Searching for default mapping file in file:/C:/Documents%20and%20Settings/maghei/Skrivbord/HibernateFilterDemo/build/
[TopLink Config]: 2007.05.30 12:52:35.380--ServerSession(14615608)--Thread(Thread[main,5,main])--The alias name for the entity class [class se.lantmateriet.ormtest.domain.User] is being defaulted to: User.
[TopLink Config]: 2007.05.30 12:52:35.380--ServerSession(14615608)--Thread(Thread[main,5,main])--The column name for element [protected int se.lantmateriet.ormtest.domain.DomainEntity.id] is being defaulted to: ID.
[TopLink Config]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--The column name for element [private java.util.UUID se.lantmateriet.ormtest.domain.DomainEntity.uuid] is being defaulted to: UUID.
[TopLink Warning]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--Ignoring default serialization on element [private java.util.UUID se.lantmateriet.ormtest.domain.DomainEntity.uuid] within entity class [class se.lantmateriet.ormtest.domain.User] since a @Convert is specified.
[TopLink Config]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--The column name for element [private java.lang.String se.lantmateriet.ormtest.domain.User.username] is being defaulted to: USERNAME.
[TopLink Config]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--The column name for element [private boolean se.lantmateriet.ormtest.domain.User.activated] is being defaulted to: ACTIVATED.
[TopLink Finest]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--property=toplink.weaving.changetracking; default value=false
[TopLink Finest]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--property=toplink.weaving.lazy; default value=true
[TopLink Finest]: 2007.05.30 12:52:35.396--ServerSession(14615608)--Thread(Thread[main,5,main])--end predeploying Persistence Unit em; state Predeployed; factoryCount 0
The interesting thing is that the spring setup completely ignores @Converter and @Convert. Why????
Thanks,
/Magnus