Hi guys, thanks for your help, I'm implementing your recommendations and
all seems to work fine.
Just one point: do I understand you correctly that I have to override
explicitly the properties set in persistence.xml, the other ones just
get the defaults as specified in the documentation.
As an example, my persistence.xml looks like this:
<persistence-unit name="SeminarEntityManager"
transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:/courseAppDS</jta-data-source>
<properties>
<property name="hibernate.dialect"
value="org.hibernate.dialect.MySQLDialect"/>
<property name="hibernate.hbm2ddl.auto"
value="update" />
</properties>
</persistence-unit>
In the initial context, I put the following line to get rid of the MySQL
dialect:
p.put("exampleDatabase.hibernate.dialect",
"org.hibernate.dialect.HSQLDialect");
If I don't do that, is the value from persistence.xml taken, or can I
get rid of this property for the initial context as well?
(The question's probably stupid... I assume that the line
p.put("exampleDatabase", "new://Resource?type=DataSource");
creates a new data source with all default parameters anyway, ignoring
the persistence.xml altogether... but what are the Hibernate default
parameters... I don't think that I fully understood what's going on
behind the scene...)
>
>I second Jean-Louis' recommendation to use just one unit.
>
>One additional approach is that nearly all aspects of the
>persistence- unit can be overridden by OpenEJB.
>
>
>1. The <jta-data-source> and <non-jta-data-source>
>
>We will automatically use the datasources you have setup in your test
>environment, we're pretty good at guessing the right datasources you
>intend. A log line will be printed saying if we had to adjust your
>persistence.xml.
>
>2. The unit <properties>
>
>You can override any property in your test setup via either system
>properties or the initial context properties. The format is:
>
> <unit-name>.<property>=<value>
>
>So for example:
>
> Properties p = new Properties();
>
>p
>.put
>(Context
>.INITIAL_CONTEXT_FACTORY
>,"org.apache.openejb.client.LocalInitialContextFactory");
>
> p.put("exampleDatabase", "new://Resource?type=DataSource");
> p.put("exampleDatabase.JdbcDriver", "org.hsqldb.jdbcDriver");
> p.put("exampleDatabase.JdbcUrl", "jdbc:hsqldb:mem:exampledb");
> // Note, if you don't configure an unmanaged datasource, we
>will
> // automatically create one for you based on the above
>datasource.
>
> // here we're setting an persistence unit property
> p.put("myUnit.hibernate.hbm2ddl.auto", "update");
>
> context = new InitialContext(p);
>
>3. Special note on "hibernate.transaction.manager_lookup_class"
>
>Nothing works if this is not set correctly to the OpenEJB specific
>class, so we take the liberty of setting it for you. There's no need
>to set it yourself.
>
>
>An note on the altdd support: we actually added this only recently on
>purpose after a bit of hesitation. Reason being is that the most
>common cases of wanting things to be "different" are taken care of
>automatically. The boring "need to use a different" database kind of
>needs are covered. It's really only when you are trying to do
>something really complicated that you need to break into the altdd
>support.
>
>Think we need to update the altdd page with a big disclaimer that
>there is an easier way to do persistence unit configuration.
>
>-David
>
>On Aug 18, 2009, at 1:06 PM, Jean-Louis MONTEIRO wrote:
>
>>
>> Hi Adrian,
>>
>> Using two persistence units seems not appropriated. Moreover,
>> defining those
>> persistence units in two different persistence.xml files can be
>> error prone.
>>
>> Regarding maven, src/main/java + src/main/resources will go to
>> target/classes so it will be deployed as an ejb module.
>> src/test/java + src/test/resources will go two a different module in
>> target/test-classes
>>
>> I can see two solutions to solve your problem (from my
>understanding).
>>
>> For both, i recommend not to use two persistence units. You only
>> need one
>> persistence unit, but you need to change the data source for tests,
>> production, ...
>>
>> 1. the first is using maven: you can define a persistence.xml
>> (src/main/filters) with strings you can dynamically change using
>> filters.
>> for example: <jta-data-source>@target.datasource@</jta-data-source>
>>
>> Then, you just need to create two profiles:
>> - test (for example) activated by default used to change the
>> datasource to
>> the test one.
>> - production (for example) used during packaging/deply phase or any
>> other by
>> using the -P switch.
>>
>> Everything is well described in the maven definitive user guide.
>>
>> 2. using alternate deployment descriptors
>> You can use 2 persistence.xml file defining the same persistence
>> unit (one
>> for test and the other for production). Then, you just have
>to set the
>> system property (altdd) to switch from one to the other.
>>
>> Hope it helps.
>> Jean-Louis
>>
>>
>>
>>
>> burriad wrote:
>>>
>>> <Second try, full problem description this time around...>
>>> Hi,
>>>
>>> I'm facing the following issue: I have to DB instances, one for
>>> testing
>>> (an in-memory HSQLDB database) and one for production (will be
>>> MySQL ,
>>> for now I use exactly the same DB). To make the switch between the
>>> two,
>>> I came up with the following setup:
>>>
>>> 1. Maven project, with OpenEJB registered for testing (I won't show
>>> the pom here)
>>> 2. One persistence.xml with two persistence units (I tried to put
>>> one persistence.xml in /src/test/resources, but it didn't got
>>> recognized
>>> during testing) .
>>> <persistence-unit name="ejb-example-openejb">
>>> <provider>org.hibernate.ejb.HibernatePersistence</provider>
>>> <jta-data-source>exampleDatabase</jta-data-source>
>>>
>>> <non-jta-data-source>exampleDatabaseUnmanaged</non-jta-data-source>
>>> <properties>
>>> <property name="hibernate.hbm2ddl.auto" value="update"/>
>>> <property
>>> name="hibernate.transaction.manager_lookup_class"
>>>
>>> value="org.apache.openejb.hibernate.TransactionManagerLookup"/>
>>> </properties>
>>> </persistence-unit>
>>> <persistence-unit name="ejb-example-openejb-testing">
>>> <provider>org.hibernate.ejb.HibernatePersistence</provider>
>>> <jta-data-source>exampleDatabase</jta-data-source>
>>>
>>> <non-jta-data-source>exampleDatabaseUnmanaged</non-jta-data-source>
>>> <properties>
>>> <property name="hibernate.hbm2ddl.auto" value="update"/>
>>> <property
>>> name="hibernate.transaction.manager_lookup_class"
>>>
>>> value="org.apache.openejb.hibernate.TransactionManagerLookup"/>
>>> </properties>
>>> </persistence-unit>
>>> 3. A test case setup with the altdd-Option activated:
>>> p.put(Context.INITIAL_CONTEXT_FACTORY,
>>> "org.apache.openejb.client.LocalInitialContextFactory");
>>>
>>> p.put("openejb.altdd.prefix", "test");
>>>
>>> p.put("exampleDatabase", "new://Resource?type=DataSource");
>>> p.put("exampleDatabase.JdbcDriver", "org.hsqldb.jdbcDriver");
>>> p.put("exampleDatabase.JdbcUrl", "jdbc:hsqldb:mem:exampledb");
>>> p.put("exampleDatabaseUnmanaged",
>>> "new://Resource?type=DataSource");
>>> p.put("exampleDatabaseUnmanaged.JdbcDriver",
>>> "org.hsqldb.jdbcDriver");
>>> p.put("exampleDatabaseUnmanaged.JdbcUrl",
>>> "jdbc:hsqldb:mem:exampledb");
>>> p.put("exampleDatabaseUnmanaged.JtaManaged", "false");
>>>
>>> context = new InitialContext(p);
>>> 4. An ejb-jar.xml and a test.ejb-jar.xml that look almost the same,
>>> besides pointing to a different persistence unit (only test.ejb-
>>> jar.xml
>>> shown here):
>>> <ejb-jar>
>>> <enterprise-beans>
>>> <session>
>>> <ejb-name>SessionFacadeImpl</ejb-name>
>>> <persistence-context-ref>
>>>
>>> <persistence-context-ref-name>persistenceContext</persistence-
>>> context-re
>>> f-name>
>>>
>>> <persistence-unit-name>ejb-example-openejb-testing</persistence-
>>> unit-nam
>>> e>
>>> </persistence-context-ref>
>>> </session>
>>> </enterprise-beans>
>>> </ejb-jar>
>>> 5. As you might have guessed, my stateless session bean looks like
>>> follows:
>>> @Stateless
>>> public class SessionFacadeImpl implements SessionFacadeLocal {
>>> @PersistenceContext(name="persistenceContext")
>>> private EntityManager em;
>>>
>>> ...
>>> }
>>>
>>> Now I get an error when I run the tests. The error message
>looks like
>>> follows:
>>> ERROR - FAIL ... null: The persistence unit "" does not exist.
>>> Update
>>> the "persistenceContext" PersistenceContext ref to one of the
>>> available
>>> units [ejb-example-openejb-testing, ejb-example-openejb] or
>declare
>>> the
>>> unit in a persistence.xml like the following:<persistence
>>> xmlns="http://java.sun.com/xml/ns/persistence";
>>> version="1.0"><persistence-unit
>>> name=""><jta-data-source>java:openejb/Resource/myDataSource</jta-
>>> data-so
>>> urce><non-jta-data-source>java:openejb/Resource/
>>> myUnmanagedDataSource</n
>>> on-jta-data-source><properties><property
>>> name="openjpa.jdbc.SynchronizeMappings"
>>> value="buildSchema(ForeignKeys=true)"/></properties></persistence-
>>> unit><
>>> /persistence>
>>>
>>> If I do as I am told an add this empty persistence unit, I
>will get
>>> an
>>> error like this:
>>> ERROR - FAIL ... null: The reference
>>> @PersistenceContext(name="persistenceContext", unitName="")
>cannot be
>>> resolved as there are 3 units with the same name. Update your
>>> unitName
>>> to one of the following: 390766514
>>> SeminarEntityManager 390766514
>>> ejb-example-openejb 390766514
>>>
>>> So, what is wrong here? Is the configuration wrong, or is it a
>>> problem
>>> with OpenEJB? Or am I down the wrong path with my setup and
>there's
>>> an
>>> easier way to have a separate DB instance for testing.
>>>
>>> Any help would be appreciated. I could narrow the problem to the
>>> point
>>> that I could see that putting a second persistence unit into
>>> persistence.xml caused the problem, so the ejb-jar.xml
>>> configuration on
>>> a single persistence unit works as outlined.
>>> Adrian Burri
>>> Software Engineering
>>>
>>>
>>>
>>>
>>
>> --
>> View this message in context:
>http://www.nabble.com/Multiple-Persistence-Units-tp25027340p250
>32565.html
>> Sent from the OpenEJB User mailing list archive at Nabble.com.
>>
>>
>
>
