jpa

mapping database link(drda) tables to entites in jpa

Hi all I'm using a oracle thin driver to connect to my database.My database links to another db(DB2) with drda specification.My problem is that I can only view the local tables of my database and map them using jpa but I select from drda in sqldeveloper and it works so the problem is definitely with my application development.What do yo...

How to do many-to-many relation between the same entity

I have an Employee entity class with (Id,Name,EmployeeType). EmployeeType entity (Id, Description) where Description can be either REGULAR/MANAGER. I am confused on how to map Employees who are of type REGULAR to their corresponding MANAGER type Employees. Should I just add an extra field to the Employee entity itself so that it now be...

JPA join table with more than one entity

Hi, I have an Entity that looks like this: public class NpcTradeGood implements Serializable, Negotiabble { private static final long serialVersionUID = 1L; @EmbeddedId protected NpcTradeGoodPK npcTradeGoodPK; @JoinColumn(name = "npc_id", referencedColumnName = "id", nullable = false, insertable = false, updatable = fals...

JPA/Hibernate entityManager.persist(..) makes the entity's collection to become null even though they are saved

I have a PurchaseEntity that has a Set inside. After doing entityManager.persist(purchaseEntity), purchaseEntity itself and purchaseItemEntity's are all saved to DB correctly. But after that entityManager.persist(purchaseEntity) call, purchaseEntity.getItems() returns null. Is this a normal behaviour of Hibernate provided entityManager...

In an OSGi environment, how are the classpaths and classloaders set up?

I'm confused about class visibility in OSGi. I'm running Apache Felix and loading the following bundles: the antlr, asm, jpa and core bundles from eclipselink an OSGi-fied jar for javax.persistence 1.99 an OSGi-fied jar with the com.mysql.jdbc driver a bundle of my own that contains annotated entity classes and a persistence.xml anothe...

Trouble Configuring JPA in Jetty

I am trying to get JPA (Toplink) configured to run in Jetty being run from the maven plugin and am getting a javax.naming.NameNotFoundException. The specifics. web.xml: <persistence-unit-ref> <persistence-unit-ref-name>persistence/mod</persistence-unit-ref-name> <persistence-unit-name>ModPU</persistence-unit-name> </persistence...

JPA/Hibernate: Can I have a Parent without annotations and a Child with

I have a requirement to create a component which can be used stand-alone or within a larger application. When used stand-alone, it should not require a database, nor any database/ORM related dependencies. When used as as part of a larger app, some of the classes will indeed be persisted to a database via JPA/Hibernate. I was thinking ...

Shound I avoid using mappedBy to keep my application stable?

Hi! I have two entities like the following: @Entity public class Trip { @OneToMany(mappedBy = "trip", fetch = FetchType.LAZY) private Set<Job> jobs = new HashSet<Job>(); } @Entity public class Job { @ManyToOne(fetch = FetchType.LAZY) private Trip trip; } The problem is that the mappedBy relationship behaves diffe...

JPA with TopLink: No META-INF/persistence.xml was found in classpath

public class LoginTest { public static void main(String[] args) { EntityManagerFactory emf = Persistence.createEntityManagerFactory("IRCBotPU"); EntityManager em = emf.createEntityManager(); em.getTransaction().begin(); Login lg = new Login(); lg.setPassword("password"); lg.setUserName("Rocky"); em.persist...

JDO integration with hibernate

in JPA, to use hibernate, the only thing need to do is moodify persitence.xml and add in hibernate configuration. May i know with JDO, can just by modifying jdoconfig.xml, able to integrate with hibernate? any reference or example on this? ...

JPA fastest way to ignore a field during persistence?

I'm essentially looking for a "@Ignore" type annotation with which I can stop a particular field from being persisted. How can this be achieved? ...

Indirectly generate sequence numbers for composite primary keys with JPA

I have a JPA entity class with a composite primary key (uid,lid) that in the database should look like this; UID | LID | ... --------------- 1 | 1 | ... 1 | 2 | ... 1 | 3 | ... 2 | 1 | ... 2 | 2 | ... 2 | 3 | ... How can I make EclipseLink/JPA generate sequence numbers on the fly, or how can I find out the high...

Query.executeUpdate() results in XAResource exception

I'm running Spring and Hibernate's implementation of JPA on Sun's GlassFish Enterprise Server with MySQL. When I try to delete stuff from the database: Query q = entityManager.createQuery("DELETE FROM SomeEntity e"); q.executeUpdate(); I get the error: Caused by: java.sql.SQLException: Error in allocating a connection. Cause: java.l...

Reading from multiple tables and populating multiple entities using JPA SqlResultSetMapping

I have been building a JSF application using JPA to access the DB. There are a number of entities. I want to create a search results screen that shows columns from more than one entity in a table. These entities do not have foreign key relationships. To achieve this I have used a EnttityManager.createNativeQuery and specified an Entity...

Getting @Id's DataType from JPA

I'm writing a library that will be used to Hibernate many types of EJBs via JPA. When loading an EJB from JPA, the library needs the datatype of the field(s) annotated with @Id. The @Id may be annotated on a superclass of the EJB. Is there a method in Hibernate or JPA that can get the datatype of @Id? I'm tempted to use reflection, b...

Wrong ordering in generated table in jpa

Hi. This (should) be a rather simple thing to do, however I am struggling. I want a table to be generated like this: id organizationNumber name However, when I look in the database, I see that the ordering is wrong. Does anybody know how I can force hibernate/jpa to generate the table with correct ordering? desc Organization; +...

JPA using multiple database schemas

I'm having a bit of trouble with one particular issue using JPA/Spring: How can I dynamically assign a schema to an entity? We have TABLE1 that belongs to schema AD and TABLE2 that is under BD. @Entity @Table(name = "TABLE1", schema="S1D") ... @Entity @Table(name = "TABLE2", schema="S2D") ... The schemas may not be hardcoded in an ...

Hiding deleted objects

Hi I have the following use case: There's a class called Template and with that class I can create instances of the ActualObject class (ActualObject copies its inital data from the Template). The Template class has a list of Product:s. Now here comes the tricky part, the user should be able to delete Products from the database but thes...

Serialization of Entity classes using Xstream

I'm using Xstream to serialize a EJB entity class to be transferred by a web service, but it also writes the database specific information in this case the following code. Is it possible to omit this information? <oracle.toplink.essentials.internal.helper.DatabaseField> <scale>0</scale> ...

How can I access private class members in Java?

I have data model classes that contain private fields which are meant to be read-only (via a getter function). These fields are set by my JPA persistence provider (eclipselink) during normal operation, using the contents of the database. For unit tests, I want to set them to fake values from a mockup of the persistence layer. How can I d...