Java Dataset.commit方法代碼示例

import com.hp.hpl.jena.query.Dataset; //導入方法依賴的package包/類
/**
 * Import the data into the data set. When a new data set is imported the old data is deleted. 
 * @param dataset
 * @param file
 */
public void loadData(Dataset dataset, String file){
    log.info("Start loading") ;
    long startTime = System.nanoTime() ;
    dataset.begin(ReadWrite.WRITE) ;
    try {
        Model m = dataset.getDefaultModel() ;
        log.info("Number of triples before loading: " + m.size());
        RDFDataMgr.read(m, file) ;
        log.info("Number of triples after loading: " + m.size());
        dataset.commit() ;
    } 
    finally { 
        dataset.end() ;
    }
    long finishTime = System.nanoTime() ;
    double time = (finishTime-startTime)/1.0e6 ;
    log.info(String.format("Finish loading - %.2fms", time)) ;
}
 

import com.hp.hpl.jena.query.Dataset; //導入方法依賴的package包/類
private static void demoOfWriteTransaction(Dataset dataset) {
	dataset.begin(ReadWrite.WRITE);

	Model model = dataset.getDefaultModel();

	ModelUtils.fillModel(model, FOAF_BASE_URI, FOAF_SCHEMA_FilePath);

	// insert foaf:me rdf:type foaf:Person
	Resource me = model.createResource(FOAF_BASE_URI + "me");
	Property rdfType = model.getProperty(Constants.RDF_TYPE_URL);
	Resource FOAFPersonClass = model.getResource(FOAF_BASE_URI + "Person");
	model.add(me, rdfType, FOAFPersonClass);
	// model.write(System.out);// for debug

	model.close();// closing the model to flush

	dataset.commit();

	dataset.end();
}
 

import com.hp.hpl.jena.query.Dataset; //導入方法依賴的package包/類
/**
 * Create a transactional in-memory dataset and load data from a given URI.
 * <p/>
 * The dataset returned by {@link RDFDataMgr#loadDataset(String)} is not transactional.
 *
 * @param uri URI of data to load
 *
 * @return a new dataset
 */
public static Dataset loadDataset(final String uri) {
  final Dataset ds = TDBFactory.createDataset();
  ds.begin(ReadWrite.WRITE);
  try {
    RDFDataMgr.read(ds, uri);
    ds.commit();
  } finally {
    ds.end();
  }
  return ds;
}
 

import com.hp.hpl.jena.query.Dataset; //導入方法依賴的package包/類
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_rdfread_write);

    TextView textView = (TextView) findViewById(R.id.rdfTextView);
    textView.setMovementMethod(new ScrollingMovementMethod());

    // create tdb dataset
    File directory = new File(getFilesDir(), "tdb_dataset");
    directory.delete();
    directory.mkdir();
    Dataset dataset = TDBFactory.createDataset(directory.getAbsolutePath()) ;
    dataset.begin(ReadWrite.WRITE);
    Model model = dataset.getDefaultModel();

    // read a turtle file from assets and write them into a tdb backed model
    try {
        InputStream skos_ttl = getAssets().open("skos.ttl");
        RDFDataMgr.read(model, skos_ttl, Lang.TURTLE);
        skos_ttl.close();
        InputStream geosparql_rdf_xml = getAssets().open("geosparql_vocab_all.rdf");
        RDFDataMgr.read(model, geosparql_rdf_xml, Lang.RDFXML);
        geosparql_rdf_xml.close();
    } catch (IOException e) {
        Log.e(TAG, e.toString());
        e.printStackTrace();
    }

    // add some example data
    String personURI    = "http://somewhere/JohnSmith";
    String fullName     = "John Smith";
    Resource johnSmith = model.createResource(personURI);
    johnSmith.addProperty(VCARD.FN, fullName);

    dataset.commit();
    dataset.end();

    // read from tdb and print triples
    dataset.begin(ReadWrite.READ);
    Query query = QueryFactory.create("SELECT * WHERE { ?s ?p ?o } LIMIT 2");
    QueryExecution qexec = QueryExecutionFactory.create(query, model);
    ResultSet results = qexec.execSelect();
    String resultString = ResultSetFormatter.asText(results);
    Log.d(TAG, resultString);

    StringWriter dump = new StringWriter();
    RDFDataMgr.write(dump, dataset, RDFFormat.JSONLD_PRETTY);

    dataset.end();
    dataset.close();

    textView.setText(dump.toString());

}
 

import com.hp.hpl.jena.query.Dataset; //導入方法依賴的package包/類
public static void main(String[] args) 
{

	Dataset dataset = TDBFactory.createDataset("/opt/fogcutter/quoddy/jenastore/triples");
	
	dataset.begin(ReadWrite.WRITE);

	// Get model inside the transaction
	Model tdbModel = dataset.getDefaultModel();
	
	
	Property rdfsLabel = tdbModel.createProperty("http://www.w3.org/2000/01/rdf-schema#", "label");
	
	
	ResIterator resIter = tdbModel.listSubjectsWithProperty(rdfsLabel, "baseOntologyLoaded");
	
	if( resIter.hasNext() )
	{
		System.out.println( "our ontology is already loaded, do nothing..." );
	}
	else
	{
	
		System.out.println( "Our ontology is NOT loaded, loading now..." );
		
		OntModel onto = null;
		try
		{
			onto = ModelFactory.createOntologyModel(OntModelSpec.OWL_MEM, tdbModel);
	
			// Load our Ontology from the OWL file on disk
			onto.read("file:ontology/sys_ontology.owl", "TURTLE");
			
			tdbModel.add(onto);
	
			dataset.commit();
	
		}
		finally
		{
			if( dataset != null )
			{
				dataset.end();
			}
		}
	}		
}
 

import com.hp.hpl.jena.query.Dataset; //導入方法依賴的package包/類
public static void main(String[] args) 
{
	Dataset dataset = TDBFactory.createDataset( "jenastore/triples" );
	
	dataset.begin(ReadWrite.WRITE);
	
	RDFDataMgr.read(dataset, "file:/development/presentations/trijug_semantic/JenaTutorial/data/input/rdfxml/customers.rdf.xml", Lang.RDFXML);
	
	dataset.commit();
	dataset.end();
	dataset.close();
	
	
	
}