Model Archetype - Osgiliath Enterprise

It’s purpose is to make the database access available, it can also exposes Dao’s as services. It’s composed of two modules: a database one and a model one.

Database module

Here you can specify your database access configuration and expose the connections as OSGI services that will be consumed by the model module. By default Derby databases are supported, but you can tweak it to support Oracle, Mysql, PostGres, HSQL… In order to declare a database, you just have to edit your [parent]/[features]/src/main/resources/[database.cfg] and tweak the properties:

    osgi.jdbc.driver.name=osgiliathderbystandalone-pool-xa #driver to use, remove the '-xa' suffix if you don't need transactions
    databaseName=${project.parent.artifactId}.model.database #name of the database
    user=APP #db user
    password=APP #db password
    dataSourceName=${project.parent.artifactId}.model.database #name with which you'll be able to reference the created datasource in your persistence.xml
    portNumber=${database.port} #Port of the DB (change it in the [parent] pom.xml
    serverName=localhost #Server host
    serverAutoStart=true #Autostarts the database server on the host, set to false if it is already started
    createDatabase=create #autocreates the database (it'll reuse it if it already exists)

Then, you just have to reference this config file in your feature.xml prefixing the deployed config file by etc/org.ops4j.datasource-

    <feature name="my.model" version="${project.version}">
        <configfile finalname="/etc/org.ops4j.datasource-[nameofyourdb].cfg">mvn:com.foo/my/${project.version}/cfg/database</configfile>
    </feature>

Defining an other kind of datasource: You must define a new feature on the parent project features list (see features sub-module), containing the OSGI compliant database driver as well as a corresponding Pax-jdbc compliant JDBC driver (you can import the corresponding features). Then, modify the osgi.bnd file of the entity module removing the org.apache.derby.jdbc package import and adding those of your driver. Finally change the dataSource bean declaration in the blueprint file. Also, if you changed something on the datasource definition, you’ll also have to modify the datasource linkage in the model module pom.xml (the parent of the daos and entities one) as well as the database credentials in the parent pom.

Entities module

Datasource connection definition

Edit the src/main/resources/META-INF/persistence.xml file of your module and change the <jta-data-source>osgi:service/jdbc/${project.parent.artifactId}.database.xa</jta-data-source> and the <non-jta-data-source> Sections (referencing the non xa exported one). If you want to disable the transactional access, you’ve also to change the ‘transaction-type’ value to ‘RESOURCE_LOCAL’

Model object definition

In order to define a new model object, you’ve got to extends the ‘AbstractEntity’ abstract class of the src/main/java folder. All Java files that are located on this folder will be ‘delombokized’ e.g they will interpret the lombok annotations and generate the according Java code. Here’s an example of a model entity:

	@Data
	// equals, hashcode, getters and setters
	@Builder
	// builder pattern
	@NoArgsConstructor
	// constructor
	@AllArgsConstructor
	// other constructor
	@Entity
	// persistence class declaration
	@XmlRootElement
	// xml marshalling
	@EqualsAndHashCode(callSuper = true)
	@ApiModel( value = "Hello Entity", description = "Hello resource representation" )
	public class HelloEntity extends AbstractEntity implements Serializable /* in order to be sendable via JMS*/{
	/**
	* Serial
	*/
	private static final transient long serialVersionUID = 6233801298404301547L;
	/**
	* Message
	*/
	@XmlElement
	// XML node
	@NotNull(message = "message must not be null")
	// Validation for null object
	@Size(min = 2, max = 12, message = "message size must be between 2 and 12")
	// size validation
	@Pattern(regexp = "[a-zA-Z0-9]+", message = "must not contain special characters")
	// pattern validation
	@ApiModelProperty( value = "The thing to greet", required = true )
	private String helloMessage;
	}

view raw HelloEntity.java hosted with ❤ by GitHub

@Data // equals, hashcode, getters and setters @Builder // builder pattern @NoArgsConstructor // constructor @AllArgsConstructor // other constructor @Entity // persistence class declaration @XmlRootElement // xml marshalling @EqualsAndHashCode(callSuper = true) @ApiModel( value = "Hello Entity", description = "Hello resource representation" ) public class HelloEntity extends AbstractEntity implements Serializable /* in order to be sendable via JMS*/{ /** * Serial */ private static final transient long serialVersionUID = 6233801298404301547L; /** * Message */ @XmlElement // XML node @NotNull(message = "message must not be null") // Validation for null object @Size(min = 2, max = 12, message = "message size must be between 2 and 12") // size validation @Pattern(regexp = "[a-zA-Z0-9]+", message = "must not contain special characters") // pattern validation @ApiModelProperty( value = "The thing to greet", required = true ) private String helloMessage; }

Then reference this class on the <class> section of the src/main/resources/META-INF/persistence.xml file

DAO module

The dao module declares method for accessing or persisting entities.

Declaring DAOs

In order to declare a Data Access Object you’ve to expose its API to others via an interface:

	/**
	* JPA accessible interface by business or route module
	* (see business module for JMS or REST export, don't forget the
	* osgi.bnd cxf package export).
	* @author charliemordant
	*/

	public interface HelloRepository extends JpaRepository<HelloEntity, Long>
	{
	/**
	* Finds by message.
	*
	* @param message
	* message
	* @return corresponding entities
	*/
	Collection<? extends HelloEntity> findByHelloObjectMessage(String message);


	}

view raw HelloObjectRepository.java hosted with ❤ by GitHub

public interface HelloObjectRepository { Collection<? extends HelloEntity> findByHelloObjectMessage( String message_p); <S extends HelloEntity> S save(S entity); List<HelloEntity> findAll(); void deleteAll(); }

Then, with the help of spring data jpa that make all the basic CRUD operations available, you’ve to code a very small implementation:

	@OsgiServiceProvider(classes = { HelloRepository.class })
	@Singleton
	@Transactional
	public class HelloJpaRepository extends DelegatingSimpleJpaRepository<HelloEntity, Long> implements HelloRepository {
	/**
	* Entity manager.
	*/

	@PersistenceContext(unitName = "myTestPu")
	private EntityManager em;
	@PersistenceUnit( unitName = "myTestPu")
	private EntityManagerFactory emf;
	@Override
	@PostConstruct
	public void postConstruct() {
	instanciateDelegateRepository(emf, em, HelloEntity.class);
	}
	}

view raw HelloObjectJpaRepository.java hosted with ❤ by GitHub

public class HelloObjectJpaRepository extends SimpleJpaRepository<HelloEntity, Long> implements HelloObjectRepository { /** * Blueprint injected entityManager */ @Setter private EntityManager entityManager; /** * Ctor * @param domainClass clazz * @param em entity Manager */ public HelloObjectJpaRepository(Class<HelloEntity> domainClass, EntityManager entityManager) { super(domainClass, entityManager); setEntityManager(entityManager); } /** * Query to find elements by message */ @Override public Collection<? extends HelloEntity> findByHelloObjectMessage( final String message_p) { final CriteriaBuilder cb = entityManager.getCriteriaBuilder(); final CriteriaQuery<HelloEntity> cq = cb.createQuery(HelloEntity.class); final Root<HelloEntity> helloObject = cq.from(HelloEntity.class); cq.select(helloObject); final Predicate where = cb.equal(helloObject.get(HelloEntity_.helloMessage), message_p); cq.where(where); final TypedQuery<HelloEntity> q = entityManager.createQuery(cq); final List<HelloEntity> result = q.getResultList(); return result; } /** * Saves an entity */ @Override public <S extends HelloEntity> S save(S entity) { return super.save(entity); } /** * gets all entities */ @Override public List<HelloEntity> findAll() { return super.findAll(); } /** * deletes all entities */ @Override public void deleteAll() { super.deleteAll(); } }

Note that the OsgiService annotation exposes this implementation to other modules (via blueprint annotation compilation processing, which exposes it via the Osgi Service registry).

Adding JMS, REST or integration Tests to the JPA module

In order to add REST or JMS support to the JPA module, remove all net.osgiliath features on the pom.xml and add this one:

<dependency>
	<groupId>net.osgiliath.framework</groupId>
	<version>${osgiliath.framework.maven.version}</version>
	<artifactId>net.osgiliath.feature.webservices or net.osgiliath.feature.routes</artifactId>
	<type>xml</type>
	<classifier>features</classifier>
</dependency>

And the same for your projects feature (in the features module of your parent pom). Then, add these lines on your osgi.bnd Import-Package section:

Require-Bundle: org.hibernate.validator
Import-Package: \
 javax.annotation;version=0,\
 !javax.transaction,\
 javax.transaction;version='[1.1,2)',\
 javax.servlet;version='[3,4)',\
 org.springframework.data.domain;resolution:=optional,\
 org.apache.camel.builder.xml,\
 org.apache.camel.model.rest,\
 org.apache.camel.support,\
 org.apache.cxf.transport.servlet,\
 org.apache.cxf.service.factory,\
 io.swagger.jaxrs.listing,\
 *

Finally, follow the REST, JMS or Itests sections of the business module documentation

Datasource connection definition

Model object definition

Declaring DAOs

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