ont-api: add RDFNodeList#contains(E) functionality + tests

Author: sszuev

src/main/java/com/github/owlcs/ontapi/jena/impl/OntListImpl.java

@@ -435,6 +435,14 @@ public ExtendedIterator<OntStatement> listSpec() {
         return Iter.flatMap(createSafeRDFListIterator(list.asNode()), this::toListStatements);
     }
 
+    @Override
+    public boolean contains(E item) {
+        RDFList list = getRDFList();
+        if (isNil(list)) return false;
+        return Iter.anyMatch(getModel().getGraph().find(Node.ANY, RDF.first.asNode(), item.asNode()),
+                t -> Iter.anyMatch(createSafeRDFListIterator(list.asNode()), x -> x.contains(t)));
+    }
+
     public ExtendedIterator<OntStatement> listContent() {
         return Iter.of(getMainStatement()).andThen(listSpec());
     }

src/main/java/com/github/owlcs/ontapi/jena/model/RDFNodeList.java

@@ -18,6 +18,7 @@
 import org.apache.jena.rdf.model.RDFNode;
 import org.apache.jena.rdf.model.Resource;
 
+import java.util.Objects;
 import java.util.Optional;
 import java.util.stream.Stream;
 
@@ -44,6 +45,21 @@ public interface RDFNodeList<E extends RDFNode> extends Resource {
      */
     Stream<E> members();
 
+    /**
+     * Answers {@code true} if the []-list contains the specified {@code element}.
+     * More formally, returns {@code true} if and only if
+     * this RDF-list contains at least one element {@code e} of the type {@link E} such that {@code element.equals(e)}.
+     *
+     * @param element {@link E}, not {@code null}
+     * @return boolean
+     */
+    default boolean contains(E element) {
+        Objects.requireNonNull(element);
+        try (Stream<E> members = members()) {
+            return members.anyMatch(element::equals);
+        }
+    }
+
     /**
      * Answers the first element of the type {@link E}.
      *

src/test/java/com/github/owlcs/ontapi/tests/jena/OntListTest.java

@@ -92,13 +92,16 @@ public void testCommonFunctionality1() {
         Assert.assertEquals(1, p2.propertyChains().count());
         Assert.assertEquals(0, p3.propertyChains().count());
         Assert.assertEquals(2, m.objectProperties().flatMap(OntObjectProperty::propertyChains).count());
+        Assert.assertTrue(list.contains(p3));
+        Assert.assertFalse(list.contains(p2));
         check(m, 2, OntObjectProperty.Named.class);
 
         list.remove();
         Assert.assertEquals(2, list.members().count());
         Assert.assertEquals(2, list.as(RDFList.class).size());
         Assert.assertFalse(list.isNil());
         Assert.assertFalse(list.members().anyMatch(p -> p.equals(p1)));
+        Assert.assertFalse(list.contains(p1));
         Assert.assertEquals(p3, list.last().orElseThrow(AssertionError::new));
         Assert.assertEquals(p3, list.first().orElseThrow(AssertionError::new));
         check(m, 2, OntObjectProperty.Named.class);
@@ -112,6 +115,9 @@ public void testCommonFunctionality1() {
         Assert.assertEquals(0, list.members().count());
         Assert.assertEquals(0, list.as(RDFList.class).size());
         Assert.assertTrue(list.isNil());
+        Assert.assertFalse(list.contains(p1));
+        Assert.assertFalse(list.contains(p2));
+        Assert.assertFalse(list.contains(p3));
         check(m, 2, OntObjectProperty.class);
     }
 
@@ -236,6 +242,7 @@ public void testMixedList() {
         Assert.assertEquals(3, list.size());
         Assert.assertEquals(2, list.members().count());
         Assert.assertEquals(3, list.addFirst(p3).members().count());
+        Assert.assertTrue(list.contains(p3));
         Assert.assertEquals(4, list.size());
         Assert.assertEquals(2, list.get(1).members().count());
         Assert.assertEquals(p3, list.first().orElseThrow(AssertionError::new));
@@ -375,6 +382,10 @@ public void testTypedList() {
         Assert.assertEquals(15, list.spec().count());
         Assert.assertEquals(Arrays.asList("Y", "B", "C", "D", "X"),
                 list.members().map(String::valueOf).collect(Collectors.toList()));
+        Assert.assertTrue(list.contains(m.createResource("X")));
+        Assert.assertFalse(list.contains(m.createLiteral("X")));
+        Assert.assertFalse(list.contains(m.createResource("Y")));
+        Assert.assertTrue(list.contains(m.createLiteral("Y")));
 
         Assert.assertEquals(2, list.get(2).removeFirst()
                 .addFirst(m.createResource("Z")).get(1)
@@ -383,6 +394,7 @@ public void testTypedList() {
         Assert.assertEquals(Arrays.asList("Y", "B", "Z", "X", "F"), list.members().map(String::valueOf).collect(Collectors.toList()));
         Assert.assertEquals(16, m.size());
         Assert.assertEquals(15, list.spec().count());
+        Assert.assertTrue(list.contains(m.createResource("Z")));
 
         list.clear();
         Assert.assertTrue(list.isNil());