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JDO Reference (JavaDoc)

Java/JDO API Reference (based on the JDO 2.2 JavaDoc) This reference contains the API documentation (similar to JavaDoc) of JDO 2.2. The content is derived from the original JDO documentation with some additions and notes. The most basic JDO types are: javax.jdo.JDOHelper j ...


JPA Metamodel API

Explains how to use the JPA Metamodel API to retrieve details on the types and attributes of the persistent object model.... fields and properties, similarly to the ability that Java reflection provides for general Java types. This page covers the following topics: ...


Is it possible to using JDO and distributed transaction?

I'am new to study JDO. Can and How I use JDO an distributed transaction?(multiple database)。 Is ObjectDB also provided JCA util just like DataNucleus? ... JCA, JTA, and JDO Transactions - Using and Understanding Java Data Objects     JDO : Usage of DataNucleus within ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ...


ObjectDB can't be activated

Hello, we are trying to activate objectdb on a virutalized debian 7 server, but do not have any success. Steps we made to activate the server: ... cd /tmp/objectdb-2.5.5_05/ java -cp bin/objectdb.jar com.objectdb.Activator entered ... ./server.sh start Run a java class with following contents EntityManagerFactory emf ...


Compile time enhancement using build.xml of a Netbeans web application

Does anybody have a complete, working example of the adaptations required in the build.xml of a Netbeans web application project to specify ObjectDB compile time enhancement, for both single file and whole project compilation ? The ObjectDB 2.3 manual gives the following tip: ... ObjectDB 2.3 manual gives the following tip: <java classname = "com.objectdb.Enhancer" fork = "true" ... = "-s c:\my-project\classes\*.class" /> </java > The (rather overwhelming) nbproject/build-impl.xml of ...


Compiled Queries and Cache

objectdb.conf has options for query results and program cache.  (objectdb.conf > database > query-cache > results and programs, http://www.objectdb.com/java/jpa/setting/database#The_query-cache_element_.) query.compile(); query.closeAll(); After code like above, are the query results and program cache still available?   ... > results and programs, http://www.objectdb.com/java/jpa/setting/database#The_query-cache_element_ .) query. compile ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ...



Instances of the type EntityType represent entity types.(Interface of JPA)


Processing thread count for 8-core server

In reference to the information here:  http://www.objectdb.com/java/jpa/setting/database#The_processing_element_   We are working with an 8-core processor.  The recommended thread count is "more than the number of cores but not too many."  What would be an appropriate number of threads for the processing thread pool in order to get good performance for our 8-core server? ... to the information here:  http://www.objectdb.com/java/jpa/setting/database#The_processing_element _   We ... ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ...


Database connection url

I'd like to run a database called db1.odb on port 6136, and simultaneously open it in the explorer. I left the conf file set as: <server> <connection port="6136" max="100" /> <data path="$objectdb/db-files" /> </server> However, I'm not sure about the connection url for the code, and for the explorer. I tried this: Transactor.emf = Persistence.createEntityManagerFactory ("$objectdb/db1.odb");... fix the connection url. See: http://www.objectdb.com/java/jpa/persistence/overview#EntityManagerFactory ObjectDB Support ObjectDB - Fast Object Database for Java (JPA/JDO) edit ...


Entity Management Config questions

Hi, the manual states the following regarding config of Entities: http://www.objectdb.com/java/jpa/setting/entities  : <cache ref="weak" level2="0mb" /> The <cache> element specifies settings of the two cache mechanisms for entities:... config of Entities: http://www.objectdb.com/java/jpa/setting/entities : <cache ref = "weak" level2 = ... blog explains the differences: http://weblogs.java.net/blog/2006/05/04/understanding-weak-references For more ... please see: http://www.google.com/search?q=java+strong+weak+soft+reference ObjectDB Support ...