OpenEJB is a lightweight EJB container which can be used to perform EJB testing. In this example we deploy an EJB that saves some data in a table.
In default mode, OpenEJB automatically uses OpenJPA as the JPA implementation. We are going to change it and use Hibernate instead.
By the time I write this post, OpenEJB 3.2.0-SNAPSHOT is the current version that supports JPA2, which is the one that's going to be used in the example. Previous versions of OpenEJB like 3.1.4 only support JPA1, so, be careful when if you come into strange and undescriptive errors and you don't know what may be going on...
So, first of all we need the following jar files:
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>ar.com.openejb</groupId> <artifactId>openejb3-example</artifactId> <version>1.0-SNAPSHOT</version> <packaging>jar</packaging> <name>openejb3-example</name> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> </properties> <repositories> <repository> <id>JBoss Developer</id> <url>https://repository.jboss.org/nexus/content/groups/developer/</url> </repository> </repositories> <dependencies> <dependency> <groupId>org.hibernate</groupId> <artifactId>hibernate-entitymanager</artifactId> <version>3.6.9.Final</version> <scope>test</scope> </dependency> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <version>4.8.2</version> <scope>test</scope> </dependency> <!-- Here we use PostgreSQL, you may use another database --> <dependency> <groupId>postgresql</groupId> <artifactId>postgresql</artifactId> <version>9.1-901.jdbc4</version> <scope>test</scope> </dependency> <dependency> <groupId>org.apache.openejb</groupId> <artifactId>openejb-core</artifactId> <version>3.2.0-SNAPSHOT</version> <scope>test</scope> </dependency> <dependency> <groupId>org.jboss.ejb3</groupId> <artifactId>jboss-ejb3-api</artifactId> <version>3.1.0</version> <scope>test</scope> </dependency> <!-- This one is to let OpenEJB log stuff --> <dependency> <groupId>org.slf4j</groupId> <artifactId>slf4j-jcl</artifactId> <version>1.6.4</version> <scope>test</scope> </dependency> </dependencies> </project>
The java.naming.factory.initial is the minimum variable requirement to start the container. Here, it is set via jndi.properties file, just make sure it is available in the classpath.
jndi.properties
#This is the minimun requirement to lauch OpenEJB java.naming.factory.initial=org.apache.openejb.client.LocalInitialContextFactory #We want OpenEJB to log everything in debug mode log4j.category.OpenEJB.options = debug log4j.category.OpenEJB.startup = debug log4j.category.OpenEJB.startup.config = debug #We tell OpenEJB to scan the whole classpath openejb.deployments.classpath.include=".*" openejb.deployments.classpath.exclude="" #Definition of the default datasource myDS=new://Resource?type=DataSource myDS.JdbcDriver=org.postgresql.Driver myDS.JdbcUrl=jdbc:postgresql://localhost:5432/openejb3-example myDS.JtaManaged=true myDS.DefaultAutoCommit=true myDS.UserName=postgres myDS.Password=123456
The service we have created where we inject an entity manager:
PersonServiceBean.java
@Stateless
public class PersonServiceBean implements PersonService {
@PersistenceContext(unitName="openejb3-example")
private EntityManager entityManager;
@Override
public Integer save(Person person) throws Exception {
entityManager.persist(person);
return person.getId();
}
}
Now we can start the context with InitialContext() which will read our jndi.properties file and start automatically the OpenEJB container and allow us to lookup services.
PersonServiceTest.java
private PersonService service;
@Before
public void init() throws NamingException {
InitialContext ctx = new InitialContext();
service = (PersonService) ctx.lookup("PersonServiceBeanLocal");
}
@Test
public void saveTest() throws Exception {
Person person = new Person();
person.setName("Rudolph");
Integer id = service.save(person);
System.out.println("The person id is " + id);
}
This is the test persistence file:
persistence.xml
<persistence version="2.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/persistence" xsi:schemalocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"> <persistence-unit name="openejb3-example" transaction-type="JTA"> <provider>org.hibernate.ejb.HibernatePersistence</provider> <class>ar.com.model.Person</class> <properties> <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" /> <property name="hibernate.hbm2ddl.auto" value="update" /> <property name="hibernate.show_sql" value="true" /> </properties> </persistence-unit> </persistence>
