Rework RSA as a utility object

1 files changed, 100 insertions, 0 deletions

diff --git a/src/main/scala/rsacomb/util/RDFoxHelpers.scala b/src/main/scala/rsacomb/util/RDFoxHelpers.scala
new file mode 100644
index 0000000..9856e27
--- /dev/null
+++ b/src/main/scala/rsacomb/util/RDFoxHelpers.scala
@@ -0,0 +1,100 @@
+package rsacomb.util
+
+import java.util.{Map => JMap, HashMap => JHashMap}
+import java.io.StringReader
+import tech.oxfordsemantic.jrdfox.Prefixes
+import tech.oxfordsemantic.jrdfox.client.{
+  ConnectionFactory,
+  ServerConnection,
+  DataStoreConnection
+}
+import tech.oxfordsemantic.jrdfox.formats.SPARQLParser
+import tech.oxfordsemantic.jrdfox.logic.expression.Resource
+import tech.oxfordsemantic.jrdfox.logic.sparql.statement.SelectQuery
+
+import rsacomb.suffix.Nth
+
+object RDFoxHelpers {
+
+  def openConnection(
+      dataStore: String,
+      opts: JMap[String, String] = new JHashMap[String, String]()
+  ): (ServerConnection, DataStoreConnection) = {
+    /* Create local server connection
+     */
+    val serverUrl = "rdfox:local"
+    val role = ""
+    val password = ""
+    val server =
+      ConnectionFactory.newServerConnection(serverUrl, role, password)
+
+    /* Create datastore connection
+     */
+    // parameters.put("owl-in-rdf-support", "relaxed")
+    // parameters.put("equality", "noUNA")
+    server.createDataStore(dataStore, "par-complex-nn", opts)
+    val data = server.newDataStoreConnection(dataStore)
+
+    (server, data)
+  }
+
+  def parseSelectQuery(
+      query: String,
+      prefixes: Prefixes = new Prefixes()
+  ): Option[SelectQuery] = {
+    val parser = new SPARQLParser(
+      prefixes,
+      new StringReader(query)
+    )
+    parser.parseSingleQuery() match {
+      case q: SelectQuery => Some(q)
+      case _              => None
+    }
+  }
+
+  def submitSelectQuery(
+      data: DataStoreConnection,
+      query: String,
+      prefixes: Prefixes = new Prefixes(),
+      opts: JMap[String, String] = new JHashMap[String, String]()
+  ): List[List[Resource]] = {
+    val cursor = data.createCursor(prefixes, query, opts)
+    var answers: List[List[Resource]] = List()
+    var mul = cursor.open()
+    while (mul > 0) {
+      val answer =
+        (0 until cursor.getArity).map(cursor.getResource(_)).toList
+      answers = answer :: answers
+      mul = cursor.advance()
+    }
+    cursor.close();
+    answers
+  }
+
+  def queryInternalPredicate(
+      data: DataStoreConnection,
+      pred: String,
+      arity: Int,
+      opts: JMap[String, String] = new JHashMap[String, String]()
+  ): List[List[Resource]] = {
+    var query = "SELECT"
+    for (i <- 0 until arity) {
+      query ++= s" ?X$i"
+    }
+    query ++= " WHERE {"
+    for (i <- 0 until arity) {
+      query ++= s" ?S rsa:${pred :: Nth(i)} ?X$i ."
+    }
+    query ++= " }"
+    submitSelectQuery(data, query, RSA.Prefixes, opts)
+  }
+
+  def closeConnection(
+      server: ServerConnection,
+      data: DataStoreConnection
+  ): Unit = {
+    server.close();
+    data.close();
+  }
+
+}