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package rsacomb
/* Java imports */
import java.io.File
import java.util.HashMap
import scala.collection.JavaConverters._
import tech.oxfordsemantic.jrdfox.client.UpdateType
import tech.oxfordsemantic.jrdfox.logic.sparql.statement.SelectQuery
/* Local imports */
import rsacomb.RSA._
object RSAComb extends App {
val help: String = """
rsacomb - combined approach for CQ answering for RSA ontologies.
USAGE
rsacomb <path/to/ontology.owl> <path/to/query.sparql>
where
the ontology is expected to be an OWL file and the (single)
query a SPARQL query file.
"""
/* Simple arguments handling
*
* TODO: use something better later on
*/
if (args.length < 2) {
println(help)
sys.exit;
}
val ontoPath = new File(args(0))
val queryPath = new File(args(1))
if (!ontoPath.isFile || !queryPath.isFile) {
println("The provided arguments are not regular files.\n\n")
println(help)
sys.exit;
}
/* Create RSA object from generic OWLOntology
*
* TODO: It might be required to check if the ontology in input is
* Horn-ALCHOIQ. At the moment we are assuming this is always the
* case.
*/
val ontology: RSAOntology = RSA.loadOntology(ontoPath)
if (ontology.isRSA) {
/* Load query */
val query = RDFoxUtil.parseQuery(
"""
SELECT ?X
WHERE {
?X a :D ;
:R ?Y .
?Y :S ?Z .
?Z a :D .
}
"""
)
/* Compute answers to query */
query match {
case Some(query) => {
// Open connection to RDFox
val (server, data) = RDFoxUtil.openConnection("AnswerComputation")
// Gather canonical model and filtering rules
val canon = ontology.canonicalModel
val filter = ontology.filteringProgram(query)
{
println("\nCanonical Model rules:")
canon.rules.foreach(println)
println("\nFiltering rules")
filter.rules.foreach(println)
println("\nQuery")
println(query)
}
// Add canonical model and filtering rules
data.addRules(canon.rules.asJava)
data.addRules(filter.rules.asJava)
def retrieveInstances(pred: String, arity: Int): Unit = {
// Build query
var query = "SELECT"
for (i <- 0 until arity) {
query ++= s" ?X$i"
}
query ++= " WHERE {"
for (i <- 0 until arity) {
query ++= s" ?S internal:${pred}_$i ?X$i ."
}
query ++= " }"
// Collect answers
RDFoxUtil.submitQuery(
data,
RSA.Prefixes,
query,
arity
)
}
// Retrieve answers
println("\nAnswers:")
retrieveInstances("ANS", filter.answer.length)
/* DEBUG: adding additional checks
*/
println("\nIndividuals:")
ontology.individuals.foreach(println)
println("\nThings:")
RDFoxUtil.submitQuery(
data,
RSA.Prefixes,
"SELECT ?X { ?X a owl:Thing }",
1
)
println("\nNIs:")
RDFoxUtil.submitQuery(
data,
RSA.Prefixes,
"SELECT ?X { ?X a internal:NI }",
1
)
// ID instances
println("\nID instances:")
retrieveInstances("ID", filter.variables.length + 2)
println("\nSameAs instances:")
RDFoxUtil.submitQuery(
data,
RSA.Prefixes,
"SELECT ?X ?Y { ?X owl:sameAs ?Y }",
2
)
// Unfiltered answers
println("\nPossible answers:")
retrieveInstances("QM", filter.variables.length)
// Cycle detected
println("\nCycle detection:")
retrieveInstances("AQ_f", filter.variables.length + 2)
retrieveInstances("AQ_b", filter.variables.length + 2)
// Forks detected
println("\nForks:")
retrieveInstances("FK", filter.variables.length)
// Spurious answers
println("\nSpurious answers")
retrieveInstances("SP", filter.variables.length)
// Close connection to RDFox
RDFoxUtil.closeConnection(server, data)
}
case None => {}
}
}
}
/* Notes:
*
* To establish a connection with a local RDFox instance, do the
* following:
*
* ```
* val serverConnection : ServerConnection = ConnectionFactory.newServerConnection("rdfox:local", "", "")
* serverConnection.createDataStore("test","seq",new HashMap())
* val dataStoreConnection : DataStoreConnection = serverConnection.newDataStoreConnection("test")
* dataStoreConnection.importData(
* UpdateType.ADDITION,
* Prefixes.s_emptyPrefixes,
* new File("./path/to/file")
* )
* ```
*/
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