onto.jena
Class Memory

java.lang.Object
  onto.jena.Memory

public class Memory
extends java.lang.Object

Jena Memory access Main functionality to access and manipulate Jena ontology models in MySQL database

Version:

0.7

Author:

Michal Laclavik, Emil Gatial (inference, connection testing)

Field Summary

java.lang.String	BASE BASE returns ontology uri
Config	config
private com.hp.hpl.jena.db.IDBConnection	conn Instanceof database connection object
private static java.lang.String	DEFAULT_MODEL_NAME Default ontology model name
private boolean	loaded State variable identifies whether model is loaded
private org.apache.log4j.Logger	log Log4j object
private com.hp.hpl.jena.ontology.OntModel	model Instance of ontological model used in memory
java.lang.String	OWL_FOOT OWL_FOOT is used to add RDF footer to Event messages comming through XML-RPC
java.lang.String	OWL_HEAD OWL_HEAD is used to add RDF, OWL and ontology headers to Event messages comming through XML-RPC
java.lang.String	RDQL_USING RDQL_USING is used in RDQL queries where we can write <ont:something> or <rdf:something> instead of full ontology uri or RDF uri
java.lang.String	SPARQL_PREFIX SPARQL_PREFIX is used in SPARQL queries where we can write <ont:something> or <rdf:something> instead of full agent ontology uri or RDF uri

Constructor Summary

Memory(java.lang.String _propertyFile, java.lang.String _name)
Constructor

Method Summary

void	closeModel() Close OWL Model and store Model in RDB if using database backend This have to be redesigned and store everything on the crash
void	createModel() Creates OWL model out of defined SOURCE_FILE in OWL database and store this model see: SOURCE_FILE, INDIVIDUALS_FILE
com.hp.hpl.jena.rdf.model.Property	createProperty(java.lang.String property) Creates ontology property out ofstring represenation
java.lang.String	getBase() Reurns the onoloy name space
com.hp.hpl.jena.db.IDBConnection	getConnection() This method returns db connection
com.hp.hpl.jena.ontology.Individual	getIndividual(java.lang.String uri) Returns individual
com.hp.hpl.jena.ontology.OntModel	getModel()
java.lang.String	getNS(java.lang.String key) Returns Namespace for given key defined in config file, in property file it search for NS_[KEY]
com.hp.hpl.jena.ontology.OntClass	getOntologyClass(java.lang.String name)
com.hp.hpl.jena.ontology.Individual	getOntologyIndividual(java.lang.String name) Returns Individual
java.lang.String	getXML(com.hp.hpl.jena.rdf.model.Resource r, java.lang.String space, java.lang.String strRes) Recursive method which writes resource with all properties recursively into string and returns it
private void	init(java.lang.String _propertyFile, java.lang.String _name)
private void	loadFiles2Model(com.hp.hpl.jena.ontology.OntModel model) Returns OWL ontological model for manipulation
void	memory2owl() Saves current content of Memory into file defined in Ontology Property file see: OUTPUT_FILE
void	performInference(java.lang.String ruleFile, boolean derivationLogging) Infers some new statements about the ontological model accoding to given rules of inference and adds inferenced model as submodel of memory
void	removeModel() Remove model from DB
void	reset() Sometimes if operation is idle MySQL connection fails and we need to reset connection and model
void	test() Prints objects from OWL model for testing purposes
void	testConnection() Tests the status of connection.
java.lang.String	translateNS(java.lang.String shortNS) Translate short NS e.g.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

config

public Config config

RDQL_USING

public java.lang.String RDQL_USING

RDQL_USING is used in RDQL queries where we can write <ont:something> or <rdf:something> instead of full ontology uri or RDF uri

SPARQL_PREFIX

public java.lang.String SPARQL_PREFIX

SPARQL_PREFIX is used in SPARQL queries where we can write <ont:something> or <rdf:something> instead of full agent ontology uri or RDF uri

BASE

public java.lang.String BASE

BASE returns ontology uri

OWL_HEAD

public java.lang.String OWL_HEAD

OWL_HEAD is used to add RDF, OWL and ontology headers to Event messages comming through XML-RPC

OWL_FOOT

public java.lang.String OWL_FOOT

OWL_FOOT is used to add RDF footer to Event messages comming through XML-RPC

DEFAULT_MODEL_NAME

private static final java.lang.String DEFAULT_MODEL_NAME

Default ontology model name

See Also:

Constant Field Values

log

private org.apache.log4j.Logger log

Log4j object

conn

private com.hp.hpl.jena.db.IDBConnection conn

Instanceof database connection object

model

private com.hp.hpl.jena.ontology.OntModel model

Instance of ontological model used in memory

loaded

private boolean loaded

State variable identifies whether model is loaded

Constructor Detail

Memory

public Memory(java.lang.String _propertyFile,
              java.lang.String _name)

Constructor

Parameters:

_propertyFile - - property file name where settings for jena memory are stored. Settings are defined according to Config

_name - name of the component

Method Detail

init

private void init(java.lang.String _propertyFile,
                  java.lang.String _name)

getBase

public java.lang.String getBase()

Reurns the onoloy name space

Returns:

name space of memory

getConnection

public com.hp.hpl.jena.db.IDBConnection getConnection()

This method returns db connection

Returns:

instance of db connection object

createModel

public void createModel()

Creates OWL model out of defined SOURCE_FILE in OWL database and store this model see: SOURCE_FILE, INDIVIDUALS_FILE

removeModel

public void removeModel()

Remove model from DB

loadFiles2Model

private void loadFiles2Model(com.hp.hpl.jena.ontology.OntModel model)

Returns OWL ontological model for manipulation

getModel

public com.hp.hpl.jena.ontology.OntModel getModel()

performInference

public void performInference(java.lang.String ruleFile,
                             boolean derivationLogging)

Infers some new statements about the ontological model accoding to given rules of inference
and adds inferenced model as submodel of memory

Parameters:

ruleFile - path to file with line delimited list of rules

derivationLogging - true/false value indicates whether to perform logging of inferenced statements
false value accelerate inferece processing

See Also:

setDerivationLogging

reset

public void reset()

Sometimes if operation is idle MySQL connection fails and we need to reset connection and model

test

public void test()

Prints objects from OWL model for testing purposes

memory2owl

public void memory2owl()

Saves current content of Memory into file defined in Ontology Property file see: OUTPUT_FILE

closeModel

public void closeModel()

Close OWL Model and store Model in RDB if using database backend This have to be redesigned and store everything on the crash

createProperty

public com.hp.hpl.jena.rdf.model.Property createProperty(java.lang.String property)

Creates ontology property out ofstring represenation

Parameters:

property - represents local name of ontology property

getIndividual

public com.hp.hpl.jena.ontology.Individual getIndividual(java.lang.String uri)

Returns individual

Parameters:

uri - URI of individual

Returns:

Individual

getOntologyIndividual

public com.hp.hpl.jena.ontology.Individual getOntologyIndividual(java.lang.String name)

Returns Individual

Parameters:

name - of the individual without namespace prefix

Returns:

Individual

getOntologyClass

public com.hp.hpl.jena.ontology.OntClass getOntologyClass(java.lang.String name)

testConnection

public void testConnection()

Tests the status of connection. If it doesn't exist then make new connection to database and initialize model

getXML

public java.lang.String getXML(com.hp.hpl.jena.rdf.model.Resource r,
                               java.lang.String space,
                               java.lang.String strRes)

Recursive method which writes resource with all properties recursively into string and returns it

Parameters:

space - is just to track levels of XML

r - resource which should be converted to XML text

getNS

public java.lang.String getNS(java.lang.String key)

Returns Namespace for given key defined in config file, in property file it search for NS_[KEY]

Parameters:

key - namespace reference key

translateNS

public java.lang.String translateNS(java.lang.String shortNS)

Translate short NS e.g. region:Region to long NS found in appropriate config file

Parameters:

shortNS -

Returns:

returns full name space