Library Version 12.1.3.0

Example6.java: SPARQL ASK query
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## Example6.java: SPARQL ASK query

This example shows a SPARQL ASK query. It inserts a triple that postulates that John is a parent of Mary. It then finds whether John is a parent of Mary.

    import com.hp.hpl.jena.graph.*;
    import com.hp.hpl.jena.query.*;
    import oracle.rdf.kv.client.jena.*;

    public class Example6
    {

      public static void main(String[] args) throws Exception
      {

    String szStoreName  = args[0];
    String szHostName   = args[1];
    String szHostPort   = args[2];
    String szModelName  = args[3];

    // Create Oracle NoSQL connection
    OracleNoSqlConnection conn
          = OracleNoSqlConnection.createInstance(szStoreName,
                                                 szHostName,
                                                 szHostPort);

    // Create model from named graph
    OracleModelNoSql model =
    OracleModelNoSql.createOracleModelNoSql(szModelName,
                                            conn);
    // Clear model
    model.removeAll();

    // Get graph from model
    OracleGraphNoSql graph = model.getGraph();

    // Add triples

    graph.add(Triple.create(Node.createURI("u:John"),
                            Node.createURI("u:parentOf"),
                            Node.createURI("u:Mary")));

    String szQuery =
              " ASK { <u:John> <u:parentOf> <u:Mary> } ";

    System.out.println("Execute ASK query " + szQuery);

    Query query = QueryFactory.create(szQuery) ;
    QueryExecution qexec = QueryExecutionFactory.create(query, model) ;

    boolean b = qexec.execAsk();
    System.out.println("Ask result = " + ((b)?"TRUE":"FALSE"));

    // Close objects
    qexec.close();
    model.close();
    conn.dispose();
      }
    }

The following are the commands to compile and run this example, as well as the expected output of the java command.

    javac -classpath ./:./jena-core-2.7.4.jar:./jena-arq-2.9.4.jar: \
    ./sdordfnosqlclient.jar:./kvclient.jar:./xercesImpl-2.10.0.jar: \
    ./slf4j-api-1.6.4.jar:./slf4j-log4j12-1.6.4.jar:./log4j/1.2.16.jar: \
    ./jena-iri-0.9.4.jar:./xml-apis-1.4.01.jar Example6.java

    javac -classpath ./:./jena-core-2.7.4.jar:./jena-arq-2.9.4.jar: \
    ./sdordfnosqlclient.jar:./kvclient.jar:./xercesImpl-2.10.0.jar: \
    ./slf4j-api-1.6.4.jar:./slf4j-log4j12-1.6.4.jar:./log4j/1.2.16.jar: \
    ./jena-iri-0.9.4.jar:./xml-apis-1.4.01.jar Example6 <store_name> \
    <host_name> <host_port> <graph_name>

    Execute ASK query ASK { <u:John> <u:parentOf> <u:Mary> }
    Ask result = TRUE

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