Merge pull request #662 from afs/jena-1806-examples
JENA-1806: Update examples
diff --git a/jena-arq/src-examples/arq/examples/aggregates/CustomAggregate.java b/jena-arq/src-examples/arq/examples/aggregates/CustomAggregate.java
index 3ab2eb0..3efb081 100644
--- a/jena-arq/src-examples/arq/examples/aggregates/CustomAggregate.java
+++ b/jena-arq/src-examples/arq/examples/aggregates/CustomAggregate.java
@@ -40,7 +40,7 @@
* <p>
* Custom aggregates must be registered before parsing the query; custom
* aggregates and custom functions have the same syntax so the to tell the
- * differenc, the parser needs to know which IRIs are custom aggregates.
+ * difference, the parser needs to know which IRIs are custom aggregates.
* <p>
* The aggregate is registered as a URI, AccumulatorFactory and default value
* for the "no groups" case.
diff --git a/jena-arq/src/main/java/org/apache/jena/system/Txn.java b/jena-arq/src/main/java/org/apache/jena/system/Txn.java
index 3ecb649..9242bd3 100644
--- a/jena-arq/src/main/java/org/apache/jena/system/Txn.java
+++ b/jena-arq/src/main/java/org/apache/jena/system/Txn.java
@@ -27,7 +27,7 @@
* <p>
* Nested transaction are not supported but calling inside an existing transaction,
* which must be compatible, (i.e. a write needs a WRITE transaction).
- * causes the exising transaction to be used.
+ * causes the existing transaction to be used.
*/
public class Txn {
diff --git a/jena-core/src-examples/jena/examples/ontology/classHierarchy/ClassHierarchy.java b/jena-core/src-examples/jena/examples/ontology/classHierarchy/ClassHierarchy.java
index 88a6f84..69ec855 100644
--- a/jena-core/src-examples/jena/examples/ontology/classHierarchy/ClassHierarchy.java
+++ b/jena-core/src-examples/jena/examples/ontology/classHierarchy/ClassHierarchy.java
@@ -21,16 +21,18 @@
package jena.examples.ontology.classHierarchy;
-// Imports
-///////////////
-import org.apache.jena.ontology.*;
-import org.apache.jena.rdf.model.*;
-import org.apache.jena.shared.PrefixMapping;
-import org.apache.jena.util.iterator.Filter;
-
import java.io.PrintStream;
import java.util.*;
+// Imports
+///////////////
+import org.apache.jena.ontology.OntClass;
+import org.apache.jena.ontology.OntModel;
+import org.apache.jena.ontology.Restriction;
+import org.apache.jena.rdf.model.AnonId;
+import org.apache.jena.rdf.model.Resource;
+import org.apache.jena.shared.PrefixMapping;
+
/**
* <p>
@@ -65,11 +67,7 @@
public void showHierarchy( PrintStream out, OntModel m ) {
// create an iterator over the root classes that are not anonymous class expressions
Iterator<OntClass> i = m.listHierarchyRootClasses()
- .filterDrop( new Filter<OntClass>() {
- @Override
- public boolean accept( OntClass r ) {
- return r.isAnon();
- }} );
+ .filterDrop( OntClass::isAnon );
while (i.hasNext()) {
showClass( out, i.next(), new ArrayList<OntClass>(), 0 );
diff --git a/jena-sdb/src-examples/sdb/examples/Ex1.java b/jena-sdb/src-examples/sdb/examples/Ex1.java
index 40fbbde..fd13b92 100644
--- a/jena-sdb/src-examples/sdb/examples/Ex1.java
+++ b/jena-sdb/src-examples/sdb/examples/Ex1.java
@@ -43,13 +43,12 @@
// The right answers will be obtained but slowly.
Dataset ds = DatasetStore.create(store) ;
- QueryExecution qe = QueryExecutionFactory.create(query, ds) ;
- try {
+ try ( QueryExecution qe = QueryExecutionFactory.create(query, ds) ) {
ResultSet rs = qe.execSelect() ;
ResultSetFormatter.out(rs) ;
- } finally { qe.close() ; }
+ }
- // Close the SDB conenction which also closes the underlying JDBC connection.
+ // Close the SDB connection which also closes the underlying JDBC connection.
store.getConnection().close() ;
store.close() ;
}
diff --git a/jena-sdb/src-examples/sdb/examples/Ex2.java b/jena-sdb/src-examples/sdb/examples/Ex2.java
index 7410941..2d33cce 100644
--- a/jena-sdb/src-examples/sdb/examples/Ex2.java
+++ b/jena-sdb/src-examples/sdb/examples/Ex2.java
@@ -51,11 +51,10 @@
Store store = SDBFactory.connectStore(conn, storeDesc) ;
Dataset ds = DatasetStore.create(store) ;
- QueryExecution qe = QueryExecutionFactory.create(query, ds) ;
- try {
+ try ( QueryExecution qe = QueryExecutionFactory.create(query, ds) ) {
ResultSet rs = qe.execSelect() ;
ResultSetFormatter.out(rs) ;
- } finally { qe.close() ; }
+ }
store.close() ;
}
}
diff --git a/jena-sdb/src-examples/sdb/examples/ExJdbcConnection.java b/jena-sdb/src-examples/sdb/examples/ExJdbcConnection.java
index 0f2baea..f99ea4b 100644
--- a/jena-sdb/src-examples/sdb/examples/ExJdbcConnection.java
+++ b/jena-sdb/src-examples/sdb/examples/ExJdbcConnection.java
@@ -73,11 +73,10 @@
Store store = StoreFactory.create(storeDesc, conn) ;
Dataset ds = DatasetStore.create(store) ;
- QueryExecution qe = QueryExecutionFactory.create(query, ds) ;
- try {
+ try ( QueryExecution qe = QueryExecutionFactory.create(query, ds) ) {
ResultSet rs = qe.execSelect() ;
ResultSetFormatter.out(rs) ;
- } finally { qe.close() ; }
+ }
// Does not close the JDBC connection.
// Do not call : store.getConnection().close() , which does close the underlying connection.
store.close() ;
diff --git a/jena-tdb/src-examples/tdb/examples/ExQuadFilter.java b/jena-tdb/src-examples/tdb/examples/ExQuadFilter.java
index 20782e3..95357b8 100644
--- a/jena-tdb/src-examples/tdb/examples/ExQuadFilter.java
+++ b/jena-tdb/src-examples/tdb/examples/ExQuadFilter.java
@@ -18,9 +18,9 @@
package tdb.examples;
-import org.apache.jena.atlas.iterator.Filter ;
-import org.apache.jena.atlas.lib.Tuple ;
+import java.util.function.Predicate;
+import org.apache.jena.atlas.lib.tuple.Tuple;
import org.apache.jena.graph.NodeFactory ;
import org.apache.jena.query.* ;
import org.apache.jena.sparql.core.DatasetGraph ;
@@ -36,7 +36,7 @@
* Can be used to exclude data from specific graphs.
* This mechanism is not limited to graphs - it works for properties or anything
* where the visibility of otherwise is determined by the elements of the quad.
- * See <a href="http://incubator.apache.org/jena/documentation/tdb/quadfilter.html">QuadFiltering</a>
+ * See <a href="http://jena.apache.org/documentation/tdb/quadfilter.html">QuadFiltering</a>
* for further details.
*/
@@ -50,7 +50,7 @@
TDB.getContext().setTrue(TDB.symUnionDefaultGraph) ;
Dataset ds = setup() ;
- Filter<Tuple<NodeId>> filter = createFilter(ds) ;
+ Predicate<Tuple<NodeId>> filter = createFilter(ds) ;
example(ds, filter) ;
}
@@ -67,7 +67,7 @@
}
/** Create a filter to exclude the graph http://example/g2 */
- private static Filter<Tuple<NodeId>> createFilter(Dataset ds)
+ private static Predicate<Tuple<NodeId>> createFilter(Dataset ds)
{
// Filtering operates at a very low level:
// Need to know the internal identifier for the graph name.
@@ -77,26 +77,24 @@
// Filter for accept/reject as quad as being visible.
// Return true for "accept", false for "reject"
- Filter<Tuple<NodeId>> filter = new Filter<Tuple<NodeId>>() {
- @Override
- public boolean accept(Tuple<NodeId> item)
+ Predicate<Tuple<NodeId>> filter = item ->
{
// Reverse the lookup as a demo
//Node n = TDBInternal.getNode(target) ;
//System.err.println(item) ;
- if ( item.size() == 4 && item.get(0).equals(target) )
+ if ( item.len() == 4 && item.get(0).equals(target) )
{
//System.out.println("Reject: "+item) ;
return false ;
}
//System.out.println("Accept: "+item) ;
return true ;
- } } ;
+ } ;
return filter ;
}
- private static void example(Dataset ds, Filter<Tuple<NodeId>> filter)
+ private static void example(Dataset ds, Predicate<Tuple<NodeId>> filter)
{
String[] x = {
"SELECT * { GRAPH ?g { ?s ?p ?o } }",
@@ -113,23 +111,21 @@
}
- private static void example(Dataset ds, String qs, Filter<Tuple<NodeId>> filter)
+ private static void example(Dataset ds, String qs, Predicate<Tuple<NodeId>> filter)
{
System.out.println() ;
Query query = QueryFactory.create(qs) ;
System.out.println(qs) ;
- QueryExecution qExec = QueryExecutionFactory.create(query, ds) ;
- // Install filter for this query only.
- if ( filter != null )
- {
- System.out.println("Install quad-level filter") ;
- qExec.getContext().set(SystemTDB.symTupleFilter, filter) ;
+ try ( QueryExecution qExec = QueryExecutionFactory.create(query, ds) ) {
+ // Install filter for this query only.
+ if ( filter != null )
+ {
+ System.out.println("Install quad-level filter") ;
+ qExec.getContext().set(SystemTDB.symTupleFilter, filter) ;
+ }
+ else
+ System.out.println("No quad-level filter") ;
+ ResultSetFormatter.out(qExec.execSelect()) ;
}
- else
- System.out.println("No quad-level filter") ;
- ResultSetFormatter.out(qExec.execSelect()) ;
- qExec.close() ;
-
}
-
}
diff --git a/jena-tdb/src-examples/tdb/examples/ExTDB4.java b/jena-tdb/src-examples/tdb/examples/ExTDB4.java
index bb9ea1a..af7dfd3 100644
--- a/jena-tdb/src-examples/tdb/examples/ExTDB4.java
+++ b/jena-tdb/src-examples/tdb/examples/ExTDB4.java
@@ -50,11 +50,9 @@
// See http://incubator.apache.org/jena/documentation/query/app_api.html
Query query = QueryFactory.create(sparqlQueryString) ;
- QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ;
- ResultSet results = qexec.execSelect() ;
- ResultSetFormatter.out(results) ;
- qexec.close() ;
-
- dataset.close();
+ try ( QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ) {
+ ResultSet results = qexec.execSelect() ;
+ ResultSetFormatter.out(results) ;
+ }
}
}
diff --git a/jena-tdb/src-examples/tdb/examples/ExTDB5.java b/jena-tdb/src-examples/tdb/examples/ExTDB5.java
index 92517d5..2b8df5c 100644
--- a/jena-tdb/src-examples/tdb/examples/ExTDB5.java
+++ b/jena-tdb/src-examples/tdb/examples/ExTDB5.java
@@ -18,53 +18,41 @@
package tdb.examples;
-import org.apache.jena.query.Dataset ;
-import org.apache.jena.query.Query ;
-import org.apache.jena.query.QueryExecution ;
-import org.apache.jena.query.QueryExecutionFactory ;
-import org.apache.jena.query.QueryFactory ;
-import org.apache.jena.query.QuerySolution ;
-import org.apache.jena.query.ResultSet ;
-import org.apache.jena.tdb.TDBFactory ;
+import org.apache.jena.query.Dataset;
+import org.apache.jena.query.Query;
+import org.apache.jena.query.QueryExecution;
+import org.apache.jena.query.QueryExecutionFactory;
+import org.apache.jena.query.QueryFactory;
+import org.apache.jena.query.QuerySolution;
+import org.apache.jena.query.ResultSet;
+import org.apache.jena.tdb.TDBFactory;
-/** Example of creating a TDB-backed model.
- * The preferred way is to create a dataset then get the mode required from the dataset.
- * The dataset can be used for SPARQL query and update
- * but the Model (or Graph) can also be used.
- *
- * All the Jena APIs work on the model.
- *
- * Calling TDBFactory is the only place TDB-specific code is needed.
- *
- * See also ExTDB_Txn1 for use with transactions.
+/**
+ * Example of creating a TDB-backed model. The preferred way is to create a dataset
+ * then get the mode required from the dataset. The dataset can be used for SPARQL
+ * query and update but the Model (or Graph) can also be used. All the Jena APIs work
+ * on the model. Calling TDBFactory is the only place TDB-specific code is needed.
+ * See also ExTDB_Txn1 for use with transactions.
*/
-public class ExTDB5
-{
- public static void main(String... argv)
- {
+public class ExTDB5 {
+ public static void main(String...argv) {
// Direct way: Make a TDB-back Jena model in the named directory.
- String directory = "MyDatabases/DB1" ;
- Dataset dataset = TDBFactory.createDataset(directory) ;
-
- // Potentially expensive query.
- String sparqlQueryString = "SELECT (count(*) AS ?count) { ?s ?p ?o }" ;
- // See http://incubator.apache.org/jena/documentation/query/app_api.html
-
- Query query = QueryFactory.create(sparqlQueryString) ;
- QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ;
- try {
- ResultSet results = qexec.execSelect() ;
- for ( ; results.hasNext() ; )
- {
- QuerySolution soln = results.nextSolution() ;
- int count = soln.getLiteral("count").getInt() ;
- System.out.println("count = "+count) ;
- }
- } finally { qexec.close() ; }
+ String directory = "MyDatabases/DB1";
+ Dataset dataset = TDBFactory.createDataset(directory);
- // Close the dataset.
- dataset.close();
-
+ // Potentially expensive query.
+ String sparqlQueryString = "SELECT (count(*) AS ?count) { ?s ?p ?o }";
+ // See http://incubator.apache.org/jena/documentation/query/app_api.html
+
+ Query query = QueryFactory.create(sparqlQueryString);
+ try (QueryExecution qexec = QueryExecutionFactory.create(query, dataset)) {
+ ResultSet results = qexec.execSelect();
+ for ( ; results.hasNext() ; ) {
+ QuerySolution soln = results.nextSolution();
+ int count = soln.getLiteral("count").getInt();
+ System.out.println("count = " + count);
+ }
+ }
}
}
diff --git a/jena-tdb/src-examples/tdb/examples/ExTDB6.java b/jena-tdb/src-examples/tdb/examples/ExTDB6.java
index 3dd2c0a..868dc8d 100644
--- a/jena-tdb/src-examples/tdb/examples/ExTDB6.java
+++ b/jena-tdb/src-examples/tdb/examples/ExTDB6.java
@@ -36,7 +36,7 @@
/** Example of single threaded use of TDB working with the Jena RDF API */
public class ExTDB6
{
- /// observe the non-http "protocol", because it is a bad precident
+ /// observe the non-http "protocol", because it is a bad precedent
/// to only use http IRI when there is no http protocol involved
public static final String MY_NS =
"x-ns://example.org/ns1/";
@@ -45,7 +45,7 @@
/// turn off the "No BGP optimizer warning"
TDB.setOptimizerWarningFlag(false);
- final IRIFactory iriFactory = IRIFactory.semanticWebImplementation();
+ final IRIFactory iriFactory = IRIFactory.iriImplementation();
final String DATASET_DIR_NAME = "data0";
final Dataset data0 = TDBFactory.createDataset( DATASET_DIR_NAME );
@@ -102,15 +102,14 @@
out.println("QueryFactory.TIME="+(t1 - t0));
t0 = System.currentTimeMillis();
- final QueryExecution qExec = QueryExecutionFactory
+ try ( QueryExecution qExec = QueryExecutionFactory
// if you query the whole DataSet,
// you have to provide a FROM in the SparQL
//.create(q, data0);
- .create(q, model);
- t1 = System.currentTimeMillis();
- out.println("QueryExecutionFactory.TIME="+(t1 - t0));
+ .create(q, model) ) {
+ t1 = System.currentTimeMillis();
+ out.println("QueryExecutionFactory.TIME="+(t1 - t0));
- try {
t0 = System.currentTimeMillis();
ResultSet rs = qExec.execSelect();
t1 = System.currentTimeMillis();
@@ -123,8 +122,6 @@
out.println("\t"+name+" := "+sol.get(name));
}
}
- } finally {
- qExec.close();
}
}
out.println("closing graph");
diff --git a/jena-tdb/src-examples/tdb/examples/ExTDB_Txn1.java b/jena-tdb/src-examples/tdb/examples/ExTDB_Txn1.java
index 57629a4..4c4a2fa 100644
--- a/jena-tdb/src-examples/tdb/examples/ExTDB_Txn1.java
+++ b/jena-tdb/src-examples/tdb/examples/ExTDB_Txn1.java
@@ -18,23 +18,20 @@
package tdb.examples;
-import org.apache.jena.query.Dataset ;
-import org.apache.jena.query.Query ;
-import org.apache.jena.query.QueryExecution ;
-import org.apache.jena.query.QueryExecutionFactory ;
-import org.apache.jena.query.QueryFactory ;
-import org.apache.jena.query.QuerySolution ;
-import org.apache.jena.query.ReadWrite ;
-import org.apache.jena.query.ResultSet ;
+import org.apache.jena.query.*;
+import org.apache.jena.system.Txn;
import org.apache.jena.tdb.TDBFactory ;
-/** Example of a READ transaction. */
+/**
+ * Example of a READ transaction.
+ * See {@link Txn#executeRead}.
+ */
public class ExTDB_Txn1
{
public static void main(String... argv)
{
- String directory = "MyDatabases/DB1" ;
- Dataset dataset = TDBFactory.createDataset(directory) ;
+ String directory = "MyDatabases/DB1";
+ Dataset dataset = TDBFactory.createDataset(directory);
// Start READ transaction.
// No updates or changes to the dataset are possible while this
@@ -42,41 +39,36 @@
// An application can have other Datasets, in the same JVM,
// tied to the same TDB database performing read or write
// transactions concurrently.
+
+ // A READ transaction is
+ // dataset.begin(ReadWrite.READ);
+ // try {
+ // ...
+ // ... The app can also call dataset.abort() or dataset.commit() here; commit is not necessary
+ // } finally { dataset.end();}
- dataset.begin(ReadWrite.READ) ;
- try
- {
+ // Use Txn.executeRead when the app knows there are no updates.
+ // Can use Txn.execute when a write is possible.
+ Txn.executeRead(dataset, ()-> {
// Do some queries
- String sparqlQueryString1 = "SELECT (count(*) AS ?count) { ?s ?p ?o }" ;
- execQuery(sparqlQueryString1, dataset) ;
-
- String sparqlQueryString2 = "SELECT * { ?s ?p ?o }" ;
- execQuery(sparqlQueryString2, dataset) ;
-
- // Can also call dataset.abort() or dataset.commit() here
- } finally
- {
- // Notify the end of the READ transaction.
- // Any use of dataset.abort() or dataset.commit() or dataset.end()
- // .end() can be called multiple times for the same .begin(READ)
- dataset.end() ;
- }
+ String sparqlQueryString1 = "SELECT (count(*) AS ?count) { ?s ?p ?o }";
+ execQuery(sparqlQueryString1, dataset);
+
+ String sparqlQueryString2 = "SELECT * { ?s ?p ?o }";
+ execQuery(sparqlQueryString2, dataset);
+ });
}
public static void execQuery(String sparqlQueryString, Dataset dataset)
{
- Query query = QueryFactory.create(sparqlQueryString) ;
- QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ;
- try {
- ResultSet results = qexec.execSelect() ;
- for ( ; results.hasNext() ; )
- {
- QuerySolution soln = results.nextSolution() ;
- int count = soln.getLiteral("count").getInt() ;
- System.out.println("count = "+count) ;
+ Query query = QueryFactory.create(sparqlQueryString);
+ try ( QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ) {
+ ResultSet results = qexec.execSelect();
+ for ( ; results.hasNext() ; ) {
+ QuerySolution soln = results.nextSolution();
+ int count = soln.getLiteral("count").getInt();
+ System.out.println("count = " + count);
}
- } finally { qexec.close() ; }
+ }
}
-
}
-
diff --git a/jena-tdb/src-examples/tdb/examples/ExTDB_Txn2.java b/jena-tdb/src-examples/tdb/examples/ExTDB_Txn2.java
index a13293d..3b74518 100644
--- a/jena-tdb/src-examples/tdb/examples/ExTDB_Txn2.java
+++ b/jena-tdb/src-examples/tdb/examples/ExTDB_Txn2.java
@@ -18,66 +18,56 @@
package tdb.examples;
-import org.apache.jena.atlas.lib.StrUtils ;
+import org.apache.jena.atlas.lib.StrUtils;
+import org.apache.jena.query.Dataset;
+import org.apache.jena.system.Txn;
+import org.apache.jena.tdb.TDBFactory;
+import org.apache.jena.update.UpdateExecutionFactory;
+import org.apache.jena.update.UpdateFactory;
+import org.apache.jena.update.UpdateProcessor;
+import org.apache.jena.update.UpdateRequest;
-import org.apache.jena.query.Dataset ;
-import org.apache.jena.query.ReadWrite ;
-import org.apache.jena.tdb.TDBFactory ;
-import org.apache.jena.update.GraphStore ;
-import org.apache.jena.update.GraphStoreFactory ;
-import org.apache.jena.update.UpdateExecutionFactory ;
-import org.apache.jena.update.UpdateFactory ;
-import org.apache.jena.update.UpdateProcessor ;
-import org.apache.jena.update.UpdateRequest ;
+/**
+ * Example of a WRITE transaction.
+ * See {@link Txn#executeRead}.
+ */
+public class ExTDB_Txn2 {
+ public static void main(String...argv) {
+ String directory = "MyDatabases/DB1";
+ Dataset dataset = TDBFactory.createDataset(directory);
-/** 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 dataset inside the write transaction.
- // 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.
+ // 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) ;
+ // A WRITE transaction is
+ // dataset.begin(ReadWrite.READ);
+ // try {
+ // ...
+ // ... dataset.abort() or dataset.commit()
+ // } finally { dataset.end();}
+ //
+
+ Txn.executeWrite(dataset, ()->{
// Do a SPARQL Update.
- String sparqlUpdateString = StrUtils.strjoinNL(
- "PREFIX . <http://example/>",
- "INSERT { :s :p ?now } WHERE { BIND(now() AS ?now) }"
- ) ;
+ 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() ;
- }
+ execUpdate(sparqlUpdateString, dataset);
+ });
}
-
- public static void execUpdate(String sparqlUpdateString, GraphStore graphStore)
- {
- UpdateRequest request = UpdateFactory.create(sparqlUpdateString) ;
- UpdateProcessor proc = UpdateExecutionFactory.create(request, graphStore) ;
- proc.execute() ;
+
+ public static void execUpdate(String sparqlUpdateString, Dataset dataset) {
+ UpdateRequest request = UpdateFactory.create(sparqlUpdateString);
+ UpdateProcessor proc = UpdateExecutionFactory.create(request, dataset);
+ proc.execute();
}
-
+
}
-
diff --git a/jena-tdb/src-examples/tdb/examples/ExTDB_Txn3.java b/jena-tdb/src-examples/tdb/examples/ExTDB_Txn3.java
index 1b6f067..93f377b 100644
--- a/jena-tdb/src-examples/tdb/examples/ExTDB_Txn3.java
+++ b/jena-tdb/src-examples/tdb/examples/ExTDB_Txn3.java
@@ -18,10 +18,10 @@
package tdb.examples;
-import org.apache.jena.query.* ;
-import org.apache.jena.sparql.core.DatasetGraph ;
-import org.apache.jena.tdb.TDBFactory ;
-import org.apache.jena.tdb.transaction.DatasetGraphTransaction ;
+import org.apache.jena.query.*;
+import org.apache.jena.sparql.core.DatasetGraph;
+import org.apache.jena.system.Txn;
+import org.apache.jena.tdb.TDBFactory;
/** Illustration of working at the DatasetGraph level.
* Normally, applications work with {@link Dataset}.
@@ -32,40 +32,31 @@
{
public static void main(String... argv)
{
- DatasetGraphTransaction dsg = (DatasetGraphTransaction)TDBFactory.createDatasetGraph() ;
+ DatasetGraph dsg = TDBFactory.createDatasetGraph();
- // Start READ transaction.
- dsg.begin(ReadWrite.READ) ;
-
- try
- {
+ // Start a transaction. It starts in "read" mode and promotes to "write" mode if necessary.
+ Txn.execute(dsg, ()->{
// Do some queries
- String sparqlQueryString1 = "SELECT (count(*) AS ?count) { ?s ?p ?o }" ;
- execQuery(sparqlQueryString1, dsg) ;
- } finally
- {
- dsg.end() ;
- }
+ String sparqlQueryString1 = "SELECT (count(*) AS ?count) { ?s ?p ?o }";
+ execQuery(sparqlQueryString1, dsg);
+ });
}
public static void execQuery(String sparqlQueryString, DatasetGraph dsg)
{
- // Add a datset wrapper to conform with the query interface.
+ // Add a dataset wrapper to conform with the query interface.
// This should not be very expensive.
- Dataset dataset = DatasetFactory.create(dsg) ;
+ Dataset dataset = DatasetFactory.wrap(dsg);
- Query query = QueryFactory.create(sparqlQueryString) ;
- QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ;
- try {
- ResultSet results = qexec.execSelect() ;
- for ( ; results.hasNext() ; )
+ Query query = QueryFactory.create(sparqlQueryString);
+ try ( QueryExecution qexec = QueryExecutionFactory.create(query, dataset) ) {
+ ResultSet results = qexec.execSelect();
+ for (; results.hasNext(); )
{
- QuerySolution soln = results.nextSolution() ;
- int count = soln.getLiteral("count").getInt() ;
- System.out.println("count = "+count) ;
+ QuerySolution soln = results.nextSolution();
+ int count = soln.getLiteral("count").getInt();
+ System.out.println("count = "+count);
}
- } finally { qexec.close() ; }
+ }
}
-
}
-
