Enterprise Java Development@TOPIC@
The setup for this exercise will use a maven archetype process to build you the shell of a JPA module to perform these exercises. The module can be created anywhere, but if you create it within a directory that already has a pom.xml, the archetype will attempt to integrate the new module as a sub-module of the existing parent.
Add the following to your .m2/settings.xml file. This will allow you to resolve the exercise archetype and set a default database for the exercise.
<profiles>
<profile>
<id>webdev-repositories</id>
<repositories>
<repository>
<id>webdev</id>
<name>ejava webdev repository</name>
<url>http://webdev.jhuep.com/~jcs/maven2</url>
<releases>
<enabled>true</enabled>
<updatePolicy>never</updatePolicy>
</releases>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
<repository>
<id>webdev-snapshot</id>
<name>ejava webdev snapshot repository</name>
<url>http://webdev.jhuep.com/~jcs/maven2-snapshot</url>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
<updatePolicy>daily</updatePolicy>
</snapshots>
</repository>
</repositories>
</profile>
</profiles>
<activeProfiles>
<activeProfile>h2db</activeProfile>
<!--
<activeProfile>h2srv</activeProfile>
-->
</activeProfiles>
Use the ejava.jpa:jpa-archetype to setup a new Maven project for this exercise. Activate the webdev-repositories profile (-Pwebdev-repositories) so that you can resolve the archetype off the Internet. The following should be run outside of the class example tree.
$ mvn archetype:generate -B -DarchetypeGroupId=info.ejava.examples.jpa -DarchetypeArtifactId=jpa-archetype -DarchetypeVersion=5.0.0-SNAPSHOT -DgroupId=myorg.relex -DartifactId=relationEx -Pwebdev-repositories [INFO] Scanning for projects... ... [INFO] ---------------------------------------------------------------------------- [INFO] Using following parameters for creating project from Archetype: jpa-archetype:5.0.0-SNAPSHOT [INFO] ---------------------------------------------------------------------------- [INFO] Parameter: groupId, Value: myorg.relex [INFO] Parameter: artifactId, Value: relationEx [INFO] Parameter: version, Value: 1.0-SNAPSHOT [INFO] Parameter: package, Value: myorg.relex [INFO] Parameter: packageInPathFormat, Value: myorg/relex [INFO] Parameter: version, Value: 1.0-SNAPSHOT [INFO] Parameter: package, Value: myorg.relex [INFO] Parameter: groupId, Value: myorg.relex [INFO] Parameter: artifactId, Value: relationEx [INFO] Project created from Archetype in dir: /Users/jim/proj/784/relationEx [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------ [INFO] Total time: 2.287 s [INFO] Finished at: 2018-08-18T12:19:05-04:00 [INFO] Final Memory: 18M/314M [INFO] ------------------------------------------------------------------------
You should now have an instantiated template for a JPA project
relationEx/
├── pom.xml
└── src
├── main
│ └── java
│ └── myorg
│ └── relex
│ └── Auto.java
└── test
├── java
│ └── myorg
│ └── relex
│ └── AutoTest.java
└── resources
├── hibernate.properties
├── log4j.xml
└── META-INF
└── persistence.xml
Verify the instantiated template builds in your environment
Activate the h2db profile (and deactivate the h2srv profile) to use an embedded file as your database. This option does not require a server but is harder to inspect database state in between tests.
relationEx]$ mvn clean test -Ph2db -P\!h2srv ... -HHH000401: using driver [org.h2.Driver] at URL [jdbc:h2:/Users/jim/proj/784/relationEx/target/h2db/ejava] ... [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------
Start your database server
$ java -jar M2_REPO/com/h2database/h2/1.4.197/h2-1.4.197.jar
Activate the h2srv profile (and deactivate the h2db profile) to use a running H2 database server. This option provides more interaction with your database but does require the server to be running.
relationEx]$ mvn clean test -P\!h2db -Ph2srv ... -HHH000401: using driver [org.h2.Driver] at URL [jdbc:h2:tcp://127.0.0.1:9092/./h2db/ejava] ... [INFO] ------------------------------------------------------------------------ [INFO] BUILD SUCCESS [INFO] ------------------------------------------------------------------------
You may now import the instantiated template into Eclipse as an "Existing Maven Project"
Put the following Junit test case in your src/test tree
package myorg.relex;
import javax.persistence.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.junit.*;
public class JPATestBase {
private static Logger log = LoggerFactory.getLogger(JPATestBase.class);
private static final String PERSISTENCE_UNIT = "relationEx-test";
private static EntityManagerFactory emf;
protected EntityManager em;
@BeforeClass
public static void setUpClass() {
log.debug("creating entity manager factory");
emf = Persistence.createEntityManagerFactory(PERSISTENCE_UNIT);
}
@Before
public void setUp() throws Exception {
log.debug("creating entity manager");
em = emf.createEntityManager();
cleanup();
em.getTransaction().begin();
}
@After
public void tearDown() throws Exception {
logger.debug("tearDown() started, em={}", em);
if (em!=null) {
EntityTransaction tx = em.getTransaction();
if (tx.isActive()) {
if (tx.getRollbackOnly() == true) { tx.rollback(); }
else { tx.commit(); }
} else {
tx.begin();
tx.commit();
}
em.close();
em=null;
}
logger.debug("tearDown() complete, em={}", em);
}
@AfterClass
public static void tearDownClass() {
log.debug("closing entity manager factory");
if (emf!=null) { emf.close(); }
}
public void cleanup() {
em.getTransaction().begin();
em.getTransaction().commit();
}
protected EntityManager createEm() {
return emf.createEntityManager();
}
}