About managed

forum_thread

Detecting ObjectDB alive

Hi, I'm wondering how best to be able to detect if ObjectDb Server is alive? For: a) from a java process - I'm guessing you could try and grab a Persistence Manager and/or listen for a Disconnection Exception?? b) from a NodeJs runtime - I'm guessing you could either try and grab the ObjectDb server port and that won't be possible as long as the Objectdb Server is running. Is there a way to polling server from TCP and/or HTTP ?   #1 2016-11-18 01:03 Hi, I'm wondering how best to be able to detect if ObjectDb Server is alive? For: a) from a j ...

 
forum_thread

Using multiple databases

Is it possible for an ObjectDB PersistenceManger/EntityManager to connect to more than one database at a time? Also, can objects in one database reference objects in another database (e.g. through globally unique identifiers)? #1 2011-08-25 10:11 Is it possible for an ObjectDB PersistenceManger/EntityManager to connect to more than one database at a time?&nb ...

 
tutorial

Step 4: Add a Servlet Class

Explains how to add a servlet that manages persistence using JPA and ObjectDB to an Eclipse Web Application. In this step we will add a servlet to manage guestbook web requests: Open the [Create Servlet] dialog box by right clicking the guest package node (in the [Package Explorer] window), selecting  New > Other... > Web > ...

 
forum_thread

Where Does ObjectDB Block/Lock?

These are questions asked in the context of the proposed architecture described in the forum thread titled, "Sample JDO Architecture for Follow Up Questions".   Questions about blocking/locking.  With my PersistenceManager multiThreaded=true architecture, I desire to know where ObjectDB is actually blocking/locking so I might adapt to achieve better concurrency. 1) Where are locks when accessing PersistenceManager by multiple threads? 2) Does it lock at PersistenceManager.currentTransaction()? #1 2016-07-25 15:41 These are questions asked in the context of the proposed architecture described in the forum thread titled, "Samp ...

 
forum_thread

mapping file is not being loaded

Hi, I am evaluating ObjectDB by using it with an in-house developed library in order to prototype its capabilities / performance. I am having a problem in that the in-house library in question reads a simple configuration file to determine available persistence units, and then bootstraps them using the JPA Persistance.createEntityManagerFactory() method and passing in the persistence unit name (again, obtained from the configuration file ). #1 2012-06-22 15:00 Hi, I am evaluating ObjectDB by using it with an in-house developed library in order to prototype its capabilitie ...

 
page

What is the Java Persistence API (JPA)?

The Java Persistence API (JPA) is a standard API for accessing databases from within Java applications. The main advantage of JPA over JDBC (the older Java API for interacting with databases) is that in JPA data is represented by classes and objects rat ...

 
api-jpa

getLockMode(entity)

Get the current lock mode for the entity instance.(Method of javax.persistence.EntityManager)

 
api-jpa

javax.persistence.PersistenceProperty

Describes a single container or persistence provider property.(Annotation of JPA)

 
api-jpa

refresh(entity, lockMode, properties)

Refresh the state of the instance from the database, overwriting changes made to the entity, if any, and lock it with respect to given lock mode type and with specified properties.(Method of javax.persistence.EntityManager)

 
api-jdo

Constants.PMF_ATTRIBUTE_CONNECTION_FACTORY2_NAME

The name of the persistence manager factory element's "connection-factory2-name" attribute.(Static Field of javax.jdo.Constants)