この例では、パラレル・ロード(複数スレッド)を使用してRDFファイルをOracle NoSQL Databaseにロードします。パラレル・ロードを使用するには、並列度(データのロードに使用されるスレッドの数)と、各スレッドによって管理されるトリプルのバケットのバッチ・サイズを指定します。この例では、Oracle NoSQL Databaseに格納されているすべてのクワッドも問い合せます。

import com.hp.hpl.jena.query.*;
import com.hp.hpl.jena.sparql.core.DatasetImpl;
import org.openjena.riot.Lang;
import oracle.rdf.kv.client.jena.*;

public class Example2b
{
  
  public static void main(String[] args) throws Exception
  {
    
String szStoreName  = args[0];
String szHostName   = args[1];
String szHostPort   = args[2];
int iBatchSize      = Integer.parseInt(args[3]);
int iDOP            = Integer.parseInt(args[4]);

System.out.println("Create Oracle NoSQL connection");
OracleNoSqlConnection conn 
= OracleNoSqlConnection.createInstance(szStoreName,
                                       szHostName, 
                                       szHostPort);
     
System.out.println("Create Oracle NoSQL datasetgraph");
OracleGraphNoSql graph = new OracleGraphNoSql(conn);
DatasetGraphNoSql datasetGraph = DatasetGraphNoSql.createFrom(graph);
   
// Close graph, as it is no longer needed
graph.close();
    
// Clear datasetgraph
datasetGraph.clearRepository();
    
// Load data from file into the Oracle NoSQL Database
DatasetGraphNoSql.load("example.nt", Lang.NQUADS, conn, 
                        "http://example.org",
                        iBatchSize, // batch size
                        iDOP); // degree of parallelism
    
// Create dataset from Oracle NoSQL datasetgraph to execute
Dataset ds = DatasetImpl.wrap(datasetGraph);
   
String szQuery = "select * where { graph ?g { ?s ?p ?o }  }";
System.out.println("Execute query " + szQuery);
    
Query query = QueryFactory.create(szQuery);
QueryExecution qexec = QueryExecutionFactory.create(query, ds);
    
try {
      ResultSet results = qexec.execSelect();
      ResultSetFormatter.out(System.out, results, query);
    }
    
finally {
      qexec.close();
    }

ds.close();
conn.dispose();
 }
}

この例をコンパイルして実行するコマンドと、想定されるJavaコマンドの出力は次のとおりです。

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 Example2b.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 Example2b <store_name> \
<host_name> <host_port> <batch_size> <dop>
        
Execute query select * where { graph ?g { ?s ?p ?o } } 

------------------------------------------
| s                                      | 
==========================================
| _:b0                                   | 
| <http://example.org/alice/foaf.rdf#me> | 
| _:b0                                   | 
| <http://example.org/alice/foaf.rdf#me> |
| _:b0                                   |
| _:b0                                   | 
| <http://example.org/alice/foaf.rdf#me> | 
| <http://example.org/bob/foaf.rdf#me>   | 
| <http://example.org/bob/foaf.rdf#me>   |
| <http://example.org/bob/foaf.rdf#me>   | 
------------------------------------------
-----------------------------------------------------
| p                                                 |
=====================================================
| <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> |
| <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> |
| <http://xmlns.com/foaf/0.1/homepage>              |
| <http://xmlns.com/foaf/0.1/knows>                 | 
| <http://www.w3.org/2000/01/rdf-schema#seeAlso>    | 
| <http://xmlns.com/foaf/0.1/name>                  | 
| <http://xmlns.com/foaf/0.1/name>                  | 
| <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> | 
| <http://xmlns.com/foaf/0.1/homepage>              | 
| <http://xmlns.com/foaf/0.1/name>                  | 
-----------------------------------------------------
------------------------------------------
| o                                      |
==========================================
| <http://xmlns.com/foaf/0.1/Person>     |
| <http://xmlns.com/foaf/0.1/Person>     |
| <http://example.org/bob/>              |
| _:b0                                   | 
| <http://example.org/bob/foaf.rdf>      |
| "Bob"                                  |
| "Alice"                                |
| <http://xmlns.com/foaf/0.1/Person>     |  
| <http://example.org/bob/>              |  
| "Bob"                                  |
------------------------------------------
------------------------------------------  
| g                                      | 
==========================================
| <http://example.org/alice/foaf.rdf>    |
| <http://example.org/alice/foaf.rdf>    | 
| <http://example.org/alice/foaf.rdf>    | 
| <http://example.org/alice/foaf.rdf>    | 
| <http://example.org/alice/foaf.rdf>    | 
| <http://example.org/alice/foaf.rdf>    | 
| <http://example.org/alice/foaf.rdf>    | 
| <http://example.org/bob/foaf.rdf>      |
| <http://example.org/bob/foaf.rdf>      |
| <http://example.org/bob/foaf.rdf>      |
------------------------------------------