ObjectDB ObjectDB

Internal Website Search

131-140 of 200 resultsRefresh

Error during closing an entity manager

We have found a workaround. We have just enhanced the entities and then it works as intended. But why this case does not perform without enhanced entities? btc_es BTC EmbeddedSystems The exception may be due to having partial enhancement. Mixing enhanced entity classes with non enhanced entity classes in

Multi-thread access to single EM's entities

If my entity classes have synchronized getters and setters, is it reliable for multiple threads to access a single EM's managed entities, as long as only the thread that created the EM interacts ... on the observable behavior of multithreaded code. When I run this example and examine the database, the entity

Entity can be found by find() but not by query

Hello, we create an entity in transaction A, commit and close the transaction. After that in transaction B we try to find the entity in the DB. But we get always only a result with em.find(), with a query it is not always possible to get the entity, sometimes we get the entity

Remove a modified entity cause an optimistic lock exception

Hello, the following examples load and modify an entity, and load and remove the same entity ... ). Can you explain the optimistic lock exception? It seems that the first level cache contains yet a dirty entity ... , entity classes, JPA wrappers, etc.) support Support I created a minimum OSGi example. Please clean

Failing to read entities under load in multithreaded tests

to read entities from the database. I've isolated this issue to a fairly simple test case (please see attached eclipse project). I have some test entities listed below. When I run a load test that creates, reads and updates these entities in multithreaded application it sometimes fails to read

ArrayIndexOutOfBoundsException with enhanced Entity

Hi! We have an two entities, the first one is something like: @Embeddable class TestEmbed {...} and the second one: @Entity class TestEntity { private TestEmbed myEmbed = null; public TestEmbed ... etc etc.). However It seems to happen only with an embeddable entity embedded within another embeddable entity like

Entity Management Config questions

Hi, the manual states the following regarding config of Entities: http://www.objectdb.com/java/jpa/setting/entities: The element specifies settings of the two cache mechanisms for entities: The ref attribute specifies the reference type for holding non

Feature suggestion: auto-detection of entities via persistence.xml extension

I am encountering problems (complexities) with EntityManager registration of entities across multiple modules in a multi-module Maven project. I have a entities under many different paths in many ... to introduce such an entity-scanning extension feature in ObjectDB ? Q2: Does it make any difference

Entity Version History

ObjectDB manages automatic entity versioning (for optimistic lock purposes). Every entity object modification is reflected by a new version number. Naturally, previous values in the entity object ... to go back in time and view old versions (and old values) of entity objects. Future versions of ObjectDB

JBOSS AS7 7.1.1 - Entity not persisted and createNamedQuery fire exception

) at com.objectdb.jpa.EMImpl.createNamedQuery(EMImpl.java:809) * entities are not getting persisted ... on the entity class and not the ejb class. So I annoted the Guest class but still called the createNamedQuery from the GuestDAO @Entity @NamedQueries( { @NamedQuery(   name="Guest.findByName

Getting Started

ObjectDB is very easy to use. Follow the Getting Started Tutorial and the Quick Tour manual chapter and in minutes you may be able to write and run first Java programs against ObjectDB.

Prior knowledge or experience in database programming (SQL, JDBC, ORM, JPA, etc.) is not required, but some background in using the Java language is essential.

Need Help?

  1. Search ObjectDB website
  2. Read the FAQ
  3. Follow the Tutorials
  4. View or post in the forum
  5. Search or file an issue
  6. Contact support