How to instruct Maven to ignore my main/resources/persistence.xml in favor of test/…?

Question

I have two persistence.xml files, for the sake of testing:

• src/main/resources/META-INF/persistence.xml
• src/test/resources/META-INF/persistence.xml

How to instruct Maven to ignore the first file during testing? Now it is not ignored since OpenEJB says:

ERROR - FAIL ... Finder: @PersistenceContext unitName has multiple matches: 
unitName "abc" has 2 possible matches.

Answer 1

Check out the alternate descriptors functionality which is aimed at what you're trying to do.

Try this setup:

• src/main/resources/META-INF/persistence.xml
• src/main/resources/META-INF/test.persistence.xml

Then you can construct OpenEJB to prefer the test.persistence.xml file by setting the openejb.altdd.prefix System or InitialContext property to test

A different possible solution could be to override the persistence unit properties in the test. With that approach you could avoid the need for a second persistence.xml which can be nice as maintaining two can be a pain.

You can use the Maven approach, but be aware that per spec the persistence provider will only look (aka scan) for @Entity beans in the exact jar or directory where the persistence.xml is found. So be keenly aware that in Maven these are two different locations:

• target/classes
• target/test-classes

EDIT More details on the overriding capabilities

You can override any property in your test setup via either system properties or the initial context properties (this includes jndi.properties files). The format is:

<unit-name>.<property>=<value>

So for example with the following persistence.xml:

<persistence>
  <persistence-unit name="movie-unit">
    <provider>org.hibernate.ejb.HibernatePersistence</provider>
    <jta-data-source>movieDatabase</jta-data-source>
    <non-jta-data-source>movieDatabaseUnmanaged</non-jta-data-source>
    <properties>
      <property name="hibernate.hbm2ddl.auto" value="create-drop"/>
      <property name="hibernate.max_fetch_depth" value="3"/>
    </properties>
  </persistence-unit>
</persistence>

You can override and add persistence unit properties in your test case. There are currently no facilities for removing them (if you have a need for that let us know – it hasn't really come up so far).

Properties p = new Properties();
p.put(Context.INITIAL_CONTEXT_FACTORY,"org.apache.openejb.client.LocalInitialContextFactory");

p.put("movie-unit.hibernate.hbm2ddl.auto", "update");
p.put("movie-unit.hibernate.dialect", "org.hibernate.dialect.HSQLDialect");

context = new InitialContext(p);

Or alternatively via a jndi.properties file

java.naming.factory.initial=org.apache.openejb.client.LocalInitialContextFactory
movie-unit.hibernate.hbm2ddl.auto = update
movie-unit.hibernate.dialect = org.hibernate.dialect.HSQLDialect

Answer 2

I think you can create two profiles in your pom.xml:

<properties>
  <environment>dev</environment>
</properties>
<profiles>
  <profile>
    <id>prod</id>
    <properties>
      <environment>test</environment>
    </properties>
  </profile>
</profiles>

After that, in your src folder, create two folders named dev/resoruces and test/resources and copy your different resources there. After that, add something like this:

<resources>
  <resource>
    <directory>${basedir}/src/main/resources</directory>
    <filtering>false</filtering>
  </resource>
  <resource>
    <directory>${basedir}/src/main/${environment}/resources</directory>
    <filtering>true</filtering>
  </resource>
</resources>

The ${basedir} depends on the command line parameter, it can be test or dev. You run the maven command like this: mvn clean package -P test.

Answer 3

I have been testing these and other similar solutions without involving the pom.xml... In my opinion, the best way to solve this issue is to have two application-context.xml (one only to be used in test classes) and to add a custom persistence unit manager bean in the test's application-context.xml. Like this example:

<bean id="pum" class="org.springframework.orm.jpa.persistenceunit.DefaultPersistenceUnitManager">
  <property name="persistenceXmlLocation">
     <value>classpath*:META-INF/test.persistence.xml</value>
  </property>
  <property name="defaultDataSource" ref="dataSource"/>
</bean>

This solution runs. :)

Answer 4

Better add both files - in general, making test/production or debug/profile/production distinction in build makes only trouble. Better try to use different perasistence unit name for production (say abc-production) and for tests (abc-tests).