docs/spring-ejb-and-jpa.adoc

= Spring EJB and JPA
:index-group: Spring
:jbake-date: 2018-12-05
:jbake-type: page
:jbake-status: published

\{note}OpenEJB 3.1 or later required\{note} This example shows
how to combine Spring, OpenEJB and Hibernate using the integration code
provided by OpenEJB. Here, OpenEJB is used as an embeddable EJB
container inside of Spring. See the link:spring.html[Spring] page for
details.

We use the basic Movie example and expand it to include more objects to
demonstrate both Spring beans, EJB Session beans, and JPA persistent
objects in one application. The premise of the example is a Cineplex
that has a number of Theaters (viewing screens), each playing a number
of Movies. The basic object layout is as follows:

Object

Type

Description

http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration/src/main/java/org/superbiz/spring/CineplexImpl.java[CineplexImpl]

@Stateless

Shows the use of `@Resource` to have Spring beans injected. Specifically,
the _Theaters_ Spring bean

http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration/src/main/java/org/superbiz/spring/Theaters.java[Theaters]

Spring bean

Simple wrapper object injected into _CineplexImpl_

http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration/src/main/java/org/superbiz/spring/Theater.java[Theater]

Spring bean

Shows that EJBs can be injected into Spring beans. Uses both the
_Movies_ EJB and the _Movie_ JPA objects

http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration/src/main/java/org/superbiz/spring/MoviesImpl.java[MoviesImpl]

@Stateful

Wraps a JPA EntityManager and provides transactional access to the
persistent _Movie_ objects

http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration/src/main/java/org/superbiz/spring/Movie.java[Movie]

@Entity

Basic JPA bean that is used both by Spring beans and EJBs. The same
_Movie_ object as in all the other persistence related examples.

http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration/src/main/java/org/superbiz/spring/AvailableMovies.java[AvailableMovies]

Spring bean

Simple object used as a clever way to seed the EntityManager (and
really, the database) with persistent _Movie_ objects

# Required jars

To setup the integration you'll need:

[arabic]
. The standard OpenEJB 3.1 libraries
. The
https://repository.apache.org/content/groups/public/org/apache/openejb/openejb-spring/3.1.2/openejb-spring-3.1.2.jar[openejb-spring-3.1.jar]
or later
. Spring 2.5 or other (any version should work)

In Maven2 this can be done by adding the following dependencies to your
pom.xml
\{snippet:id=required|url=openejb3/examples/spring-integration/pom.xml|lang=xml}
For other environments, you can simply link:downloads.html[download an
openejb-3.1.zip] or later and include all the jars under the lib/
directory in your classpath. Then download and add the
[openejb-spring-3.1.jar|http://people.apache.org/repo/m2-ibiblio-rsync-repository/org/apache/openejb/openejb-spring/3.1/openejb-spring-3.1.jar]
along with your Spring jars.

# The Spring xml

Bootstrapping and Configuring OpenEJB is fairly simple.
\{snippet:id=bootstrapping|url=openejb3/examples/spring-integration/src/main/resources/movies.xml|lang=xml}
As well, you can optionally declare any resources or containers.
Anything declarable as a or in the openejb.xml can instead be declared
in the Spring xml file as shown here.
\{snippet:id=resources|url=openejb3/examples/spring-integration/src/main/resources/movies.xml|lang=xml}
And finally our Spring beans.
\{snippet:id=pojos|url=openejb3/examples/spring-integration/src/main/resources/movies.xml|lang=xml}
{title= Don't forget}
\{snippet:id=annotations|url=openejb3/examples/spring-integration/src/main/resources/movies.xml|lang=xml}
It allows various annotations to be detected in bean classes: Spring's
@Required and `@Autowired`, as well as JSR 250's `@PostConstruct`,
@PreDestroy and `@Resource` (if available), JAX-WS's `@WebServiceRef` (if
available), EJB3's `@EJB` (if available), and JPA's `@PersistenceContext`
and `@PersistenceUnit` (if available). Alternatively, you may choose to
activate the individual BeanPostProcessors for those annotations.
\{note}

# The Code

In efforts to keep the example page somewhat short, we'll show just
three beans, each demonstrating a particular relationship.

The first is the CineplexImpl EJB which shows EJB -> Spring.
\{snippet:id=code|url=openejb3/examples/spring-integration/src/main/java/org/superbiz/spring/CineplexImpl.java|lang=java}

The second is the Theater Spring bean which shows Spring -> EJB.
\{snippet:id=code|url=openejb3/examples/spring-integration/src/main/java/org/superbiz/spring/Theater.java|lang=java}

The last is the AvailableMovies Spring bean which Shows Spring -> EJB ->
JPA
\{snippet:id=code|url=openejb3/examples/spring-integration/src/main/java/org/superbiz/spring/AvailableMovies.java|lang=java}

# The TestCase

The JUnit TestCase uses a ClassPathXmlApplicationContext to load the
Spring ApplicationContext. Anything that loads your Spring xml file
should work fine. The following code would work a plain java app as
well.

\{snippet:id=code|url=openejb3/examples/spring-integration/src/test/java/org/superbiz/spring/MoviesTest.java|lang=java}

# Running

The source for this example can be downloaded from svn via:

$ svn co
http://svn.apache.org/repos/asf/tomee/tomee/trunk/examples/spring-integration

Then, in the "spring-integration" directory, run:

$ mvn clean install

Which should create output like the following.

[source,java]
----
-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running org.superbiz.spring.MoviesTest
log4j:WARN No appenders could be found for logger
----

(org.springframework.context.support.ClassPathXmlApplicationContext).
log4j:WARN Please initialize the log4j system properly. Apache OpenEJB
3.1 build: 20081009-03:31 http://tomee.apache.org/ INFO - openejb.home =
/Users/dblevins/work/openejb3/examples/spring-integration INFO -
openejb.base = /Users/dblevins/work/openejb3/examples/spring-integration
INFO - Configuring Service(id=Default JDK 1.3 ProxyFactory,
type=ProxyFactory, provider-id=Default JDK 1.3 ProxyFactory) INFO -
Configuring Service(id=MovieDatabase, type=Resource, provider-id=Default
JDBC Database) INFO - Configuring Service(id=MovieDatabaseUnmanaged,
type=Resource, provider-id=Default JDBC Database) INFO - Found EjbModule
in classpath:
/Users/dblevins/work/openejb3/examples/spring-integration/target/classes
INFO - Beginning load:
/Users/dblevins/work/openejb3/examples/spring-integration/target/classes
INFO - Configuring enterprise application: classpath.ear INFO -
Configuring Service(id=Default Stateless Container, type=Container,
provider-id=Default Stateless Container) INFO - Auto-creating a
container for bean CineplexImpl: Container(type=STATELESS, id=Default
Stateless Container) INFO - Auto-linking resource-ref
'org.superbiz.spring.CineplexImpl/theaters' in bean CineplexImpl to
Resource(id=theaters) INFO - Configuring Service(id=Default Stateful
Container, type=Container, provider-id=Default Stateful Container) INFO
- Auto-creating a container for bean Movies: Container(type=STATEFUL,
id=Default Stateful Container) INFO - Configuring
PersistenceUnit(name=movie-unit,
provider=org.hibernate.ejb.HibernatePersistence) INFO - Enterprise
application "classpath.ear" loaded. INFO - Assembling app: classpath.ear
INFO - PersistenceUnit(name=movie-unit,
provider=org.hibernate.ejb.HibernatePersistence) INFO -
Jndi(name=CineplexImplLocal) --> Ejb(deployment-id=CineplexImpl) INFO -
Jndi(name=MoviesLocal) --> Ejb(deployment-id=Movies) INFO - Created
Ejb(deployment-id=Movies, ejb-name=Movies, container=Default Stateful
Container) INFO - Created Ejb(deployment-id=CineplexImpl,
ejb-name=CineplexImpl, container=Default Stateless Container) INFO -
Deployed Application(path=classpath.ear) INFO - Exported EJB Movies with
interface org.superbiz.spring.Movies to Spring bean MoviesLocal INFO -
Exported EJB CineplexImpl with interface org.superbiz.spring.Cineplex to
Spring bean CineplexImplLocal Tests run: 1, Failures: 0, Errors: 0,
Skipped: 0, Time elapsed: 3.141 sec

[source,properties]
----
Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0
----