package com.franz.agbase.examples;
import com.franz.agbase.*;
public class AGNamespaces {
/**
* Demonstrates basic use of namespaces in triples
*
* @param args unused
* @throws AllegroGraphException
*/
public static void main(String[] args) throws AllegroGraphException {
// Connect to server, which must already be running.
AllegroGraphConnection ags = new AllegroGraphConnection();
try {
ags.enable();
} catch (Exception e) {
throw new AllegroGraphException("Server connection problem", e);
}
// Create fresh triple-store for this example.
AllegroGraph ts = ags.renew("namespaces", AGPaths.TRIPLE_STORES);
// Add a triple without using namespaces
ts.addStatement("<http://example.org/c>",
"<http://example.org/p>",
"<http://example.org/d>");
// Register your namespaces
// Note that rdf, owl, and some others come pre-registered
ts.registerNamespace("ex","http://example.org/");
ts.registerNamespace("xsd", "http://www.w3.org/2001/XMLSchema#");
// Create a URI using a namespace and show it
URINode a = (URINode)ts.addPart("!ex:a");
AGUtils.showURI(a);
// Create a Literal using a namespace
LiteralNode lit = (LiteralNode)ts.addPart("!\"42\"^^xsd:integer");
// Add some triples to the store using namespaces
ts.addStatement(a,"!ex:p", lit);
ts.addStatement("!ex:b","!ex:p", "!ex:c");
ts.addStatement("!ex:p","!rdf:type", "!owl:TransitiveProperty");
// Retrieve some triples without using namespaces
TriplesIterator it = ts.getStatements(false,null,"<http://example.org/p>",null);
System.out.println("Triples with predicate http://example.org/p:");
AGUtils.showTriples(it);
// Now using namespaces
it = ts.getStatements(false,null,"!ex:p",null);
System.out.println("Triples with predicate ex:p");
AGUtils.showTriples(it);
// Close the triple store and disconnect from the server.
ts.closeTripleStore();
ags.disable();
}
}
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