I'm trying to use DRY in my persistence.xml file in different persistence units.
I have the following persistence.xml (it's just one file):
<persistence-unit name="siteAPU" transaction-type="JTA">
<jta-data-source>java:/siteADS</jta-data-source>
<class>package.name.Subs</class>
<class>package.name.SubsRef</class>
<class>package.name.SubsLoc</class>
...
<persistence-unit name="siteBPU" transaction-type="JTA">
<jta-data-source>java:/siteBDS</jta-data-source>
<class>package.name.Subs</class>
<class>package.name.SubsRef</class>
<class>package.name.SubsLoc</class>
...
You can see I have two different persistence units and I have the same classes being persisted.
Is there a way I can programmatically generate the persistence.xml file and don't repeat the content inside each persistence unit?
create a orm file:
<persistence-unit name="YOU_PU" ...>
<provider>YOU_PROVIDER</provider>
<mapping-file>orm.xml</mapping-file>
Inside the ORM file you will write the entities.
There is a sample here: https://github.com/uaihebert/uaicriteria/blob/master/src/test/resources/orm.xml
Related
I'm trying to create a layered web proyect with an EAR. I divided the Entities from the DataAccess in order to only allow DataAccess to be called by BusinessLogic.
I'm actually getting this exception:
Object: co.edu.icesi.i2trading.entities.Statetype#21397ba0 is not a known entity type.
And I found here that I need to create a persistence.xml in the EAR, but I can't really understand how.
Sharing a persistence unit across components in a .ear file
I tried placing the XML file in the Configuration Files:
And referencing the jar with <jar-files> in the persistence.xml;
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="I2TradingDataAccessPU" transaction-type="JTA">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/I2DataSource</jta-data-source>
<jar-file>../I2TradingEntities.jar</jar-file>
<jar-file>../../I2TradingEntities.jar</jar-file>
<shared-cache-mode>NONE</shared-cache-mode>
<properties>
<property name="eclipselink.target-server" value="None"/>
<!-- <property name="eclipselink.logging.level" value="ALL"/> -->
<property name="eclipselink.logging.level" value="WARNING"/>
</properties>
</persistence-unit>
</persistence>
With no success. Any idea why? I'm very new to Web Developing and this is getting to my nerves.
I'm also getting this WARNING in the persistence.xml's DESIGN tab:
I believe that the instruction jar-file interprets any path from the file that holds the persistence.xml... So, your configuration specifies that the Entities JAR are siblings of your EAR file.
The best (and easy) solution for your problem is to put the given persistence.xmlat the META-INF folder of your I2TradingEntities.jar and remove the <jar-file> instructions from it ... This will instruct the Application Server to create a PersistenceContext called "I2TradingDataAccessPU" and to detect any #Entity Class contained in that JAR.
I am using Hibernate Configuration in my persistence.xml. I want two persistence units. One for persisting or editing to the db. And the second persistence unit` will only have read access to db.
Database-readonly will be able to perform Only Read Operation to database.
<persistence-unit name="Database-readonly">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<shared-cache-mode>ENABLE_SELECTIVE</shared-cache-mode>
<validation-mode>CALLBACK</validation-mode>
<properties>
.........
.........
<properties>
Database-Persist will be able to perform editing to database (persist, modify or delete)
<persistence-unit name="Database-Persist">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<shared-cache-mode>ENABLE_SELECTIVE</shared-cache-mode>
<validation-mode>CALLBACK</validation-mode>
<properties>
.........
.........
<properties>
Is there any property in Hibernate configuration that will enable me to implement this ??.
I want to implement this because at the time of reading no transactional lock will be enabled to the database, which means multiple reading can be enabled to the EntityManager.
Question :- Is there any property in Hibernate configuration that will enable me to implement this ??.
I have created a Hibernate / JPA project and I'd like to create entities from tables.
While the tool works like a charm selecting a pure Hibernate configuration, in the JPA mode it does not work, claiming the absence of the persistence unit
As shown in the following photo, the persistence unit is located in the folder /src/main/resources/META-INF
This is the code of persistence.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="socialsports" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistenceProvider</provider>
<jta-data-source>jdbc/LiveDataSource</jta-data-source>
</persistence-unit>
</persistence>
This is the result of my attempt to run Hibernate tools to generate entities:
Since it only doesn't work in JPA mode, the use of the deprecated org.hibernate.ejb.HibernatePersistenceProvider could be a problem. Try org.hibernate.jpa.HibernatePersistenceProvider instead.
I'm getting the error "Class "test2" is mapped, but is not included in any" in eclipse, however the class is included in persistence xml.
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0"
xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="test1">
<class>com.test.domains.test1</class>
<properties>
<!-- properties for schema1 here -->
</properties>
</persistence-unit>
<persistence-unit name="test2">
<class>com.test.test2</class>
<properties>
<!-- properties for schema 2 here -->
</properties>
</persistence-unit>
</persistence>
Why does this error appear. Do I have to configure it different for 2 db schemas?
Eclipse (or more specifically Dali) do have limitation, it does not support two persistence units. That is also told in their pages:
Currently Dali only supports one Persistence Unit and one Persistence
XML file per project. Other configurations can exist in a JPA project,
but the validation and defaults processing may not be correct when
multiple persistence units are used.
What it comes to JPA itself, persistence.xml seems to becorrect. There is no need to add same class to two persistence units.
We created some libraries that all our projects will use, this libraries will provide the basic functionality of all our systems (login, some manage, etc). But the application itself could use another database.
What we did was to create the Persistence.xml with two persist units. And package all the core library entities in a jar called "LN-model.jar" and all of the entities of out test app in "App-model.jar". But for some reason we still obtain the following message.
Could not resolve a persistence unit corresponding to the persistence-context-ref-name [x.x.x.x.listener.InicializadorListener/em] in the scope of the module called [gfdeploy#/Users/zkropotkine/WORK/SeguridadCore/dist/gfdeploy/SeguridadCore-war_war]. Please verify your application.
Here's our Persistence.xml
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
<persistence-unit name="x" transaction-type="JTA">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/x</jta-data-source>
<jar-file>App-model.jar</jar-file>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties>
</properties>
</persistence-unit>
<persistence-unit name="y" transaction-type="JTA">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>jdbc/y</jta-data-source>
<jar-file>LN-model.jar</jar-file>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties/>
</persistence-unit>
By the way we put the Persistence.xml in a jar, that we add to our Enterprise Project (EAR).
The problem is that the JPA does not know which is the persistence unit to use. when you have only one persistence unit this problem does not occur. To fix do the following:
You need to specify a persistence unit : #PersistenceContext(unitName="...") in the Ejb that do not have
You can add the annotations:
#PersistenceUnit(name = "x")
EntityManagerFactory entityManagerFactory;
#PersistenceContext(unitName = "y")
EntityManager entityManager;
Or you can create it manually:
EntityManagerFactory emfA = Persistence.createEntityManagerFactory("x", properties);
EntityManagerFactory emfB = Persistence.createEntityManagerFactory("y", properties);
For more details, please see the following link: https://docs.oracle.com/html/E25034_01/usingmultipledbs.htm
is very useful, to me helped me!