...
| Code Block |
|---|
| language | xml |
|---|
| title | pom.xml (partial) for Hibernate |
|---|
|
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>${hibernate-version}</version>
<exclusions>
<exclusion>
<!-- omit Geronimo JPA spec to avoid conflict with Hibernate JPA spec -->
<groupId>org.apache.geronimo.specs</groupId>
<artifactId>geronimo-jpa_2.0_spec</artifactId>
</exclusion>
</exclusions>
</dependency> |
Configuring JPA
The persistence.xml file is the standard configuration file in JPA used to define the persistence units. Tapestry reads this file to create the EntityManagerFactory. The following example demonstrates a persistence.xml file.
| Code Block |
|---|
| language | xml |
|---|
| lang | xml |
|---|
| title | persistence.xml |
|---|
|
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="2.0">
<persistence-unit name="DemoUnit" transaction-type="RESOURCE_LOCAL">
<properties>
<property name="javax.persistence.jdbc.driver" value="org.h2.Driver" />
<property name="javax.persistence.jdbc.url" value="jdbc:h2:mem:test" />
<property name="javax.persistence.jdbc.user" value="sa" />
<property name="eclipselink.ddl-generation" value="create-tables"/>
<property name="eclipselink.logging.level" value="fine"/>
</properties>
</persistence-unit>
</persistence> |
...
With Tapestry, configuring JPA is can be much simpler than as described in by the JPA specification. Tapestry allows you to configure the EntityManagerFactory programmatically, without writing any XML. Imagine For example, imagine that you want to use JDBC connections managed by the container and provided through JNDI. The resulting persistence descriptor might look like this:
| Code Block |
|---|
| language | xml |
|---|
| lang | xml |
|---|
| title | persistence.xml |
|---|
|
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence"
version="2.0">
<persistence-unit name="JTAUnit" transaction-type="RESOURCE_LOCAL">
<non-jta-data-source>
jdbc/JPATest
<source>jdbc/JPATest</non-jta-data-source>
<properties>
<property name="eclipselink.ddl-generation" value="create-tables"/>
<property name="eclipselink.logging.level" value="fine"/>
</properties>
</persistence-unit>
</persistence> |
Now let's see how to provide the same configuration without XML. The following demonstrates an equivalent JPA configuration.
| Code Block |
|---|
| language | java |
|---|
| title | AppModule.java (partial) |
|---|
|
public class AppModule {
@Contribute(EntityManagerSource.class)
public static void configurePersistenceUnitInfos(MappedConfiguration<String,PersistenceUnitConfigurer> cfg) {
PersistenceUnitConfigurer configurer = new PersistenceUnitConfigurer() {
public void configure(TapestryPersistenceUnitInfo unitInfo) {
unitInfo.nonJtaDataSource("jdbc/JPATest")
.addProperty("eclipselink.ddl-generation", "create-tables")
.addProperty("eclipselink.logging.level", "fine");
}
};
cfg.add("JTAUnit", configurer);
}
} |
...
Alternatively, you can use the @Inject annotation to get the EntityManager injected into a page or component, as shown in the following example.
| Code Block |
|---|
| language | java |
|---|
| title | CreateAddress.java |
|---|
|
public class CreateAddress {
@Inject
private EntityManager entityManager;
@Property
private Address address;
@CommitAfter
void onSuccess() {
entityManager.persist(address);
}
} |
...