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forum_thread

Adding EntityListener Throws Unexpected Internal Exception

I tried adding EntityListener for a entity class and an exception was thrown. I followed similar as mentioned on the documentation but no luck. My entity class looks like below: ... exception ( Error 990 ) Generated by Java HotSpot ( TM ) 64-Bit Server VM 1.8.0 ( on Linux ... java .lang.NullPointerException: null java .lang.NullPointerException at com.objectdb.o.ANT.R ( ANT. java ...

 
forum_thread

Database size is much larger than expected (x2)

I store images into objectdb. The schema is : <URI>::=(<sUrl>, <cMark>, <iSize>, <baBody>, <id>) <sUrl>::=String <cMark>::=char <iSize>::=int <baBody>::=byte[] <id>::=@ID So simple a class will fail after 155,648 insertions with -Xmx1432m, ... to commit transaction: Java heap space (error 613)         at com.objectdb.jpa.EMImpl.commit(EMImpl.java:277)         at image.URIReader.read(URIReader.java:84)         at ...

 
forum_thread

JPA vs JDO - which is more efficient for OneToMany queries?

I'm curious about the trade offs between JDO and JPA. Seems to me that JDO will perform better and be statically typed. For example: Assume there are Customers and Orders.... as demonstrated and explained at http://www.objectdb.com/java/jpa/entity/fields#Inverse_Fields . A query will still be executed (i.e. ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ...

 
forum_thread

Searching lists within objects

Hi everyone,  I've a problem with searching on lists. I'm uncertain as to what the best form is, so I've created a maven project with all the classes and a unit test showing my issue. Pretty much I want to search using cb.isMember passing an object. This however does NOT work. I'm uncertain how the database is doing its matching, but it looks to me like it matches using objectids, which means you can only match isMember if you have a database object. This does not help as I'm never going to have the real object at search time. ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ... exception ( Error 990 ) Generated by Java HotSpot ( TM ) 64 - Bit Server VM 1.6.0_20 ( on ...

 
forum_thread

OutOfMemoryError on search after update on DB created with DB Doctor

It looks like there may be an issue with the DB files created with DB Doctor in recovery mode. This is the scenario that results in the OutOfMemory exception problem (using Object DB 2.5.4_04): 1. We instruct Object DB to create a 1Gb DB file on initial start-up using: <database> <size initial="1024mb" resize="256mb" page="2kb" /> This happens as expected. ... we get: Exception in thread "Thread-30" java. lang . OutOfMemoryError : Java heap space at java. util . Arrays . copyOfRange ( ...

 
forum_thread

Problem with byte arrays in JDO - internal exception

This code generates an internal exception: ... package spiffy. test ;   import java. util . List ; import javax. jdo . JDOHelper ; ... exception ( Error 990 ) Generated by Java HotSpot ( TM ) 64 - Bit Server VM 1.8.0_131 ( on ...

 
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Consulting and Training

... offer two structured training courses: Master the Java Persistence API This course covers the JPA specification in depth ...

 
forum_thread

a second mapping-file is ignored in persistence.xml by enhancer

Hello Support-Team, we have a problem with the enhancer. In the persistence.xml are two mapping-files: <mapping-file>META-INF/orm.xml</mapping-file> <mapping-file>META-INF/ormreq.xml</mapping-file> We start the enhancer and the entities of orm.xml will be enhanced by following output: ... by following output: enhancer: [ java ] [ ObjectDB 2.6.0_02 Enhancer ] [ java ] 3 persistable types have been enhanced: [ java ...

 
tutorial

Getting Started with JPA and Eclipse

Getting started tutorial for quick start with using Java Persistence API (JPA) in Eclipse.... - x and y . For this tutorial, besides the Java JDK (5 or above) and the Eclipse IDE (either Eclipse IDE for Java EE Developers or Eclipse IDE for Java Developers), you only need to ...

 
issue

Use temporary files to enable very large transactions

We have transactions in which many objects are created. These objects are no longer needed in the current transaction after creation. Unfortunately, we will receive an OutOfMemory exception because the objects are kept in the first level cache of ObjectDB. In the forum thread http://www.objectdb.com/database/forum/921 on post #4 you wrote, that ObjectDB should support very large transactions in further version. Can you implement it that ObjectDB used temporary files? ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ...