scheme support for concepts/ontologies

HIStream-SKOS/examples/test-ontology.ttl

@@ -84,6 +84,7 @@ dwh:String a owl:Restriction ;
 
 :OtherSub a skos:Concept ;
 	skos:inScheme	:OtherScheme ;
+	skos:inScheme	:TestScheme ;
 	skos:broader	:OtherTop ;
 	skos:prefLabel "OtherSub_label_en"@en ;
 	skos:notation	"other" .

HIStream-SKOS/src/main/java/de/sekmi/histream/ontology/skos/ConceptImpl.java

@@ -120,6 +120,17 @@ public class ConceptImpl implements Concept {
 			throw new OntologyException(e);
 		}
 	}
+
+	@Override
+	public String[] getSchemes() throws OntologyException {
+		ArrayList<String> ids = new ArrayList<>();
+		try {
+			store.forEachObject(this.res, SKOS.IN_SCHEME, scheme -> ids.add(scheme.stringValue()));
+		} catch (RepositoryException e) {
+			throw new OntologyException(e);
+		}
+		return ids.toArray(new String[ids.size()]);
+	}
 	
 	
 

HIStream-SKOS/src/main/java/de/sekmi/histream/ontology/skos/Store.java

@@ -170,8 +170,10 @@ public class Store implements Ontology, Plugin {
 		// if this.scheme is null, top concepts of all schemes are returned
 		return getRelatedConcepts(this.scheme, SKOS.HAS_TOP_CONCEPT);
 	}
-	public Concept[] getTopConcepts(String schemeURI)throws OntologyException{
-		return getRelatedConcepts(repo.getValueFactory().createURI(schemeURI), SKOS.HAS_TOP_CONCEPT);
+	
+	@Override
+	public Concept[] getTopConcepts(String scheme)throws OntologyException{
+		return getRelatedConcepts(repo.getValueFactory().createURI(scheme), SKOS.HAS_TOP_CONCEPT);
 	}
 	private Concept[] getRelatedConcepts(Resource subject, URI predicate)throws OntologyException{
 		RepositoryResult<Statement> rr;

HIStream-SKOS/src/test/java/de/sekmi/histream/ontology/skos/OntologyTest.java

@@ -24,6 +24,16 @@ public class OntologyTest {
 		store.setConceptScheme(NS_PREFIX+"TestScheme");
 	}
 
+	@Test
+	public void testGetSchemes() throws OntologyException{
+		Concept c = store.getConceptByNotation("other");
+		Assert.assertNotNull(c);
+		String[] schemes = c.getSchemes();
+		Assert.assertNotNull(schemes);
+		Assert.assertEquals(2, schemes.length);
+		// TODO verify scheme set (order is irrelevant)
+	}
+
 	@Test
 	public void getConceptByIdTest() throws OntologyException{
 		Assert.assertNull(store.getConceptByNotation("notfound"));
@@ -126,7 +136,6 @@ public class OntologyTest {
 			Concept c = store.getConceptByNotation("Type");
 			System.out.println("Concept:"+c);
 		}
-		
 	}
 
 }

histream-core/src/main/java/de/sekmi/histream/ontology/Concept.java

@@ -41,6 +41,14 @@ public interface Concept {
 	 */
 	String[] getIDs() throws OntologyException;
 	
+	/**
+	 * Get the schemes to which this concept belongs.
+	 * A concept may belong to no scheme. In this case an empty array is returned.
+	 * @return scheme URIs
+	 * @throws OntologyException on error
+	 */
+	String[] getSchemes() throws OntologyException;
+	
 	/**
 	 * Get the concept's preferred label for a given locale.
 	 * 

histream-core/src/main/java/de/sekmi/histream/ontology/Ontology.java

@@ -23,6 +23,13 @@ public interface Ontology extends Closeable{
 	 * @throws OntologyException for ontology errors
 	 */
 	public Concept[] getTopConcepts() throws OntologyException;
+	/**
+	 * Return the top concepts of this ontology in the specified scheme
+	 * @param scheme scheme to which all returned top concepts belong 
+	 * @return top concepts
+	 * @throws OntologyException for ontology errors
+	 */
+	public Concept[] getTopConcepts(String scheme) throws OntologyException;
 	
 	/**
 	 * Returns the time when this ontology was last modified.