/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package tdb.examples;
import org.apache.jena.atlas.lib.StrUtils ;
import com.hp.hpl.jena.query.Dataset ;
import com.hp.hpl.jena.query.ReadWrite ;
import com.hp.hpl.jena.tdb.TDBFactory ;
import com.hp.hpl.jena.update.GraphStore ;
import com.hp.hpl.jena.update.GraphStoreFactory ;
import com.hp.hpl.jena.update.UpdateExecutionFactory ;
import com.hp.hpl.jena.update.UpdateFactory ;
import com.hp.hpl.jena.update.UpdateProcessor ;
import com.hp.hpl.jena.update.UpdateRequest ;
/** Example of a WRITE transaction. */
public class ExTDB_Txn2
{
public static void main(String... argv)
{
String directory = "MyDatabases/DB1" ;
Dataset dataset = TDBFactory.createDataset(directory) ;
// Start WRITE transaction.
// It's possible to read from the datet inside the write transaction.
// An application can have other Datasets, in the same JVM,
// tied to the same TDB database performing read
// transactions concurrently. If another write transaction
// starts, the call of dataset.begin(WRITE) blocks until
// existing writer finishes.
dataset.begin(ReadWrite.WRITE) ;
try
{
GraphStore graphStore = GraphStoreFactory.create(dataset) ;
// Do a SPARQL Update.
String sparqlUpdateString = StrUtils.strjoinNL(
"PREFIX . <http://example/>",
"INSERT { :s :p ?now } WHERE { BIND(now() AS ?now) }"
) ;
execUpdate(sparqlUpdateString, graphStore) ;
dataset.commit() ;
// Or call .abort()
} finally
{
// Notify the end of the transaction.
// The transaction was finished at the point .commit or .abort was called.
// .end will force an abort() if no previous call to .commit() or .abort()
// has occurred, so .end() help manage track the state of the transaction.
// .end() can be called multiple times for the same .begin(WRITE)
dataset.end() ;
}
}
public static void execUpdate(String sparqlUpdateString, GraphStore graphStore)
{
UpdateRequest request = UpdateFactory.create(sparqlUpdateString) ;
UpdateProcessor proc = UpdateExecutionFactory.create(request, graphStore) ;
proc.execute() ;
}
}