Introduction

The latest release of JOPA fixes an issue in SPARQL query parser, which problems with property paths used together with variables.

In addition, it brings support of setting the in-memory store used by the Jena and RDF4J OntoDriver at runtime. This means that the application is able to set a different in-memory store than the one it was initially connected to. This may be useful when the application sets up a memory store and populates it with some predefined data and then wants to access it from JOPA.

The latest release of JOPA contains several bug fixes and improvements in the Jena driver. The most notable change is the support for reloading file-based storage in OntoDriver. This allows the application to reload data which might have been changed externally.

The reload is supported by the ReloadableDataSource, which can be unwrapped from an EntityManagerFactory. The following example shows this:

final EntityManagerFactory emf = // initialization of the Persistence
// Do some stuff
emf.unwrap(ReloadableDataSource.class).reload();

Note that the reloading happens outside any running transactions.

A new release of JOPA is out and it contains a long awaited feature - implementation of the Jena OntoDriver. It allows to access Jena-based storage (e.g. TDB) from JOPA, further extending capabilities of JOPA.

An example project using the Jena driver will be published in https://github.com/kbss-cvut/jopa-examples soon.

This is a maintenance release. It fixes a bug in the clone building process, which caused errors when entities with circular references were encountered.

The next release will introduce a beta version of the Jena OntoDriver, which is currently under development.