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---+ Virtuoso Jena Provider
%TOC%
---++ What is Jena?
Jena is an open source Semantic Web framework for Java. It provides an API to extract data from and write to RDF graphs.
The graphs are represented as an abstract "model". A model can be sourced with data from files, databases, URIs or a
combination of these. A Model can also be queried through SPARQL and updated through SPARUL.
---++ What is the Virtuoso Jena Provider?
The Virtuoso Jena RDF Data Provider is a fully operational Native Graph Model Storage Provider for the Jena Framework,
which enables Semantic Web applications written using the Jena RDF Frameworks to directly query the Virtuoso RDF Quad
Store. Providers are available for the latest [[http://jena.sourceforge.net/][Jena]] 2.6.x and 2.10.x versions.
%BR%%BR%
 %BR%%BR%
---++ Setup
---+++ Prerequisites
Download the latest Virtuoso Jena Provider for your Jena framework version,
Virtuoso JDBC 3 Driver, Jena Framework, and associated classes and sample programs.
* Note: The Jena Provider is explicitly bound to the Virtuoso JDBC 3 Driver. You cannot use the
Virtuoso JDBC 4 Driver for this purpose at this time.
* The version of the Jena Provider (virt_jena.jar) can be verified with the command:
$ java -jar virt_jena.jar
OpenLink Virtuoso(TM) Provider for Jena(TM) Version 2.6.2 [Build 1.2]
* Files contained in the zip files are generally older than specifically linked downloads (e.g., the Virtuoso JDBC
Driver, virtjdbc3.jar), so don't replace if prompted during extraction. Instead, rename the file extracted
from the zip, and compare their versions to be sure you keep only the most recent.
$ java -cp virtjdbc3.jar virtuoso.jdbc3.Driver
OpenLink Virtuoso(TM) Driver for JDBC(TM) Version 3.x [Build 3.57]
$ java -cp virtjdbc3.fromzip.jar virtuoso.jdbc3.Driver
OpenLink Virtuoso(TM) Driver for JDBC(TM) Version 3.x [Build 3.11]
---+++ Compiling Jena Sample Programs
1 Edit the sample programs VirtuosoSPARQLExampleX.java, where X =
{1,2,3,4,5,6,7,8,9,13}. Set the JDBC connection strings therein to point to a valid Virtuoso Server
instance, using the form:
"jdbc:virtuoso://<virtuoso-hostname-or-IP-address>[:<data port>]/charset=UTF-8/log_enable=2", "<username>", "<password>"
For example,
"jdbc:virtuoso://localhost:1111/charset=UTF-8/log_enable=2", "dba", "dba"
* Use charset=UTF-8 to ensure compatibility with non-Western codepages or character sets
such as Cyrillic
* Use log_enable=2 to turn on row-level autocommit, important when processing large RDF
data sets
1 Ensure your active CLASSPATH includes full paths to all of the following files
* jena.jar
* arq.jar
* virt_jena.jar
* virtjdbc3.jar
1 Compile the Jena Sample applications using the following command:
javac VirtuosoSPARQLExample*.java
---++ Testing
Once the Provider classes and sample program have been successfully compiled, the Provider can be tested using the
included sample programs.
---+++ Prerequisites
Ensure your active CLASSPATH includes the full path to the directory containing the compiled
VirtuosoSPARQLExample*.class files, as well as to each of the following files --
* icu4j_3_4.jar
* iri.jar
* xercesImpl.jar
* axis.jar
* commons-logging-1.1.1.jar
* jena.jar
* arq.jar
* virtjdbc3.jar
* virt_jena.jar
If you've extracted the zips into the same directory where you compiled the example files, a command like this
should do the job --
export CLASSPATH=`pwd`:`pwd`/*.jar:$CLASSPATH
---+++ The Tests
1 [[VirtJenaSPARQLExample1][Example 1]] returns the contents of the RDF Quad store of the
targeted Virtuoso instance, with the following command:
java VirtuosoSPARQLExample1
1 [[VirtJenaSPARQLExample2][Example 2]] reads in the contents of the following FOAF URIs --
http://kidehen.idehen.net/dataspace/person/kidehen#this
http://www.w3.org/People/Berners-Lee/card#i
http://demo.openlinksw.com/dataspace/person/demo#this
-- and returns the RDF data stored, with the following command:
java VirtuosoSPARQLExample2
1 [[VirtJenaSPARQLExample3][Example 3]] performs simple addition and deletion operation on the content of
the triple store, with the following command:
java VirtuosoSPARQLExample3
1 [[VirtJenaSPARQLExample4][Example 4]] demonstrates the use of the graph.contains method for
searching triples, with the following command:
java VirtuosoSPARQLExample4
1 [[VirtJenaSPARQLExample5][Example 5]] demonstrates the use of the graph.find method for
searching triples, with the following command:
java VirtuosoSPARQLExample5
1 [[VirtJenaSPARQLExample6][Example 6]] demonstrates the use of the graph.getTransactionHandler
method, with the following command:
java VirtuosoSPARQLExample6
1 [[VirtJenaSPARQLExample7][Example 7]] demonstrates the use of the graph.getBulkUpdateHandler
method, with the following command:
java VirtuosoSPARQLExample7
1 [[VirtJenaSPARQLExample8][Example 8]] demonstrates how to insert triples into a graph, with the following
command:
java VirtuosoSPARQLExample8
1 [[VirtJenaSPARQLExample9][Example 9]] demonstrates the use of the CONSTRUCT, DESCRIBE,
and ASK SPARQL query forms, with the following command:
java VirtuosoSPARQLExample9
1 [[VirtJenaSPARQLExample13][Example 13]] demonstrates the use of inference rules with the following command:
java VirtuosoSPARQLExample13
---++ Javadoc API Documentation
The [[http://docs.openlinksw.com/jena/][Javadoc API Documentation for the Jena Provider]] covers the complete set of
classes, interfaces, and methods implemented by the provider.
---++ Notes
---+++ Bypass Jena/ARQ parser
To use Virtuoso-specific SPARQL extensions (such as bif:contains), queries must bypass the Jena/ARQ
parser and go straight to the Virtuoso server. This is done by using the VirtuosoQueryExecutionFactory.create()
method, instead of and without the Jena-specific QueryFactory.create() method, which always invokes the
Jena/ARQ parser, which in turn rejects any Virtuoso-specific extensions. Thus one would execute a query as follows to
bypass the Jena parser --
VirtuosoQueryExecution vqe = VirtuosoQueryExecutionFactory.create (query, set);
vqe.execSelect();
-- rather than --
Query sparql = QueryFactory.create(query);
VirtuosoQueryExecution vqe = VirtuosoQueryExecutionFactory.create (sparql, set);
vqe.execSelect();
CategoryRDF CategoryOpenSource CategoryVirtuoso CategoryVOS CategoryJena CategoryDocumentation
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---+ Virtuoso Jena Provider
%TOC%
---++ What is Jena?
Jena is an open source Semantic Web framework for Java. It provides an API to extract data from and write to RDF graphs.
The graphs are represented as an abstract "model". A model can be sourced with data from files, databases, URIs or a
combination of these. A Model can also be queried through SPARQL and updated through SPARUL.
---++ What is the Virtuoso Jena Provider?
The Virtuoso Jena RDF Data Provider is a fully operational Native Graph Model Storage Provider for the Jena Framework,
which enables Semantic Web applications written using the Jena RDF Frameworks to directly query the Virtuoso RDF Quad
Store. Providers are available for the latest [[http://jena.sourceforge.net/][Jena]]
2.6.x and 2.10.x versions.
%BR%%BR%%BR%%BR%
---++ Setup
---+++ Prerequisites
Download the latest Virtuoso Jena Provider for your Jena framework version,
Virtuoso JDBC Driver, Jena Framework, and associated classes and sample programs.
* Note: You must use a matching set of Jena Provider and JDBC Driver.
* The Jena Provider for Jena 2.6 requires the Virtuoso JDBC 3 Driver.
* The Jena Provider for Jena 2.10 requires the Virtuoso JDBC 4 Driver.
%BR%%BR%
* The version of the Jena Provider (
virt_jena.jar) can be verified thus:
$ java -jar ./virt_jena2.jar
OpenLink Virtuoso(TM) Provider for Jena(TM) Version 2.10.1 [Build 1.10]
$ java -jar ./virt_jena.jar
OpenLink Virtuoso(TM) Provider for Jena(TM) Version 2.6.2 [Build 1.10]
* Files contained in the zip files are generally older than specifically linked downloads (e.g., the Virtuoso JDBC
Driver, virtjdbc3.jar), so don't replace if prompted during extraction. Instead, rename the file extracted
from the zip, and compare their versions to be sure you keep only the most recent.
$ java -cp ./virtjdbc3.jar virtuoso.jdbc3.Driver
OpenLink Virtuoso(TM) Driver for JDBC(TM) Version 3.x [Build 3.62]
$ java -cp ./virtjdbc3.fromzip.jar virtuoso.jdbc3.Driver
OpenLink Virtuoso(TM) Driver for JDBC(TM) Version 3.x [Build 3.11]
---+++ Compiling Jena Sample Programs
1 Edit the sample programs VirtuosoSPARQLExampleX.java, where X =
{1,2,3,4,5,6,7,8,9,13}. Set the JDBC connection strings therein to point to a valid Virtuoso Server
instance, using the form:
"jdbc:virtuoso://<virtuoso-hostname-or-IP-address>[:<data port>]/charset=UTF-8/log_enable=2", "<username>", "<password>"
For example,
"jdbc:virtuoso://localhost:1111/charset=UTF-8/log_enable=2", "dba", "dba"
* Use charset=UTF-8 to ensure compatibility with non-Western codepages or character sets
such as Cyrillic
* Use log_enable=2 to turn on row-level autocommit, important when processing large RDF
data sets
1 Ensure your active CLASSPATH includes full paths to all of the following files
* jena.jar
* arq.jar
* virt_jena.jar
* virtjdbc3.jar
1 Compile the Jena Sample applications using the following command:
javac VirtuosoSPARQLExample*.java
---++ Testing
Once the Provider classes and sample program have been successfully compiled, the Provider can be tested using the
included sample programs.
---+++ Prerequisites
Ensure your active CLASSPATH includes the full path to the directory containing the compiled
VirtuosoSPARQLExample*.class files, as well as to each of the following files --
* icu4j_3_4.jar
* iri.jar
* xercesImpl.jar
* axis.jar
* commons-logging-1.1.1.jar
* jena.jar
* arq.jar
* virtjdbc3.jar
* virt_jena.jar
If you've extracted the zips into the same directory where you compiled the example files, a command like this
should do the job --
export CLASSPATH=`pwd`:`pwd`/*.jar:$CLASSPATH
---+++ The Tests
1 [[VirtJenaSPARQLExample1][Example 1]] returns the contents of the RDF Quad store of the
targeted Virtuoso instance, with the following command:
java VirtuosoSPARQLExample1
1 [[VirtJenaSPARQLExample2][Example 2]] reads in the contents of the following FOAF URIs --
http://kidehen.idehen.net/dataspace/person/kidehen#this
http://www.w3.org/People/Berners-Lee/card#i
http://demo.openlinksw.com/dataspace/person/demo#this
-- and returns the RDF data stored, with the following command:
java VirtuosoSPARQLExample2
1 [[VirtJenaSPARQLExample3][Example 3]] performs simple addition and deletion operation on the content of
the triple store, with the following command:
java VirtuosoSPARQLExample3
1 [[VirtJenaSPARQLExample4][Example 4]] demonstrates the use of the graph.contains method for
searching triples, with the following command:
java VirtuosoSPARQLExample4
1 [[VirtJenaSPARQLExample5][Example 5]] demonstrates the use of the graph.find method for
searching triples, with the following command:
java VirtuosoSPARQLExample5
1 [[VirtJenaSPARQLExample6][Example 6]] demonstrates the use of the graph.getTransactionHandler
method, with the following command:
java VirtuosoSPARQLExample6
1 [[VirtJenaSPARQLExample7][Example 7]] demonstrates the use of the graph.getBulkUpdateHandler
method, with the following command:
java VirtuosoSPARQLExample7
1 [[VirtJenaSPARQLExample8][Example 8]] demonstrates how to insert triples into a graph, with the following
command:
java VirtuosoSPARQLExample8
1 [[VirtJenaSPARQLExample9][Example 9]] demonstrates the use of the CONSTRUCT, DESCRIBE,
and ASK SPARQL query forms, with the following command:
java VirtuosoSPARQLExample9
1 [[VirtJenaSPARQLExample13][Example 13]] demonstrates the use of inference rules with the following command:
java VirtuosoSPARQLExample13
---++ Javadoc API Documentation
Javadocs covers the complete set of classes, interfaces, and methods implemented by the provider:
* [[http://docs.openlinksw.com/jena/][Javadoc API Documentation for the Jena 2.6 Provider]]
* [[http://docs.openlinksw.com/jena2/][Javadoc API Documentation for the Jena 2.10+ Provider]]
---++ Notes
---+++ Bypass Jena/ARQ parser
To use Virtuoso-specific SPARQL extensions (such as bif:contains), queries must bypass the Jena/ARQ
parser and go straight to the Virtuoso server. This is done by using the VirtuosoQueryExecutionFactory.create()
method, instead of and without the Jena-specific QueryFactory.create() method, which always invokes the
Jena/ARQ parser, which in turn rejects any Virtuoso-specific extensions. Thus one would execute a query as follows to
bypass the Jena parser --
VirtuosoQueryExecution vqe = VirtuosoQueryExecutionFactory.create (query, set);
vqe.execSelect();
-- rather than --
Query sparql = QueryFactory.create(query);
VirtuosoQueryExecution vqe = VirtuosoQueryExecutionFactory.create (sparql, set);
vqe.execSelect();
CategoryRDF CategoryOpenSource CategoryVirtuoso CategoryVOS CategoryJena CategoryDocumentation
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![[RDF Data]](/fct/images/sw-rdf-blue.png)
![[cxml]](/fct/images/cxml_doc.png)
![[csv]](/fct/images/csv_doc.png)
![[text]](/fct/images/ntriples_doc.png)
![[turtle]](/fct/images/n3turtle_doc.png)
![[ld+json]](/fct/images/jsonld_doc.png)
![[rdf+json]](/fct/images/json_doc.png)
![[rdf+xml]](/fct/images/xml_doc.png)
![[atom+xml]](/fct/images/atom_doc.png)
![[html]](/fct/images/html_doc.png)
