Update delta link unit test

Author: Ndiritu

src/test/java/com/microsoft/graph/core/tasks/PageIteratorTest.java

@@ -179,18 +179,34 @@ void given_CollectionPage_Without_NextLink_Property_It_Iterates_Across_Pages() t
     void given_CollectionPage_Delta_Link_Property_It_Iterates_Across_Pages() throws ReflectiveOperationException, ApiException {
         TestEventsDeltaResponse originalPage = new TestEventsDeltaResponse();
         originalPage.setValue(new LinkedList<>());
-        originalPage.setOdataDeltaLink("http://localhost/events?$skip=11");
+        originalPage.setOdataNextLink("http://localhost/events?$skip=11");
         int inputEventCount = 17;
         for(int i = 0; i < inputEventCount; i++) {
             TestEventItem testEventItem = new TestEventItem();
             testEventItem.setSubject("Test Event: " + i);
             originalPage.getValue().add(testEventItem);
         }
 
-        Function<TestEventItem, Boolean> processPageItemCallback = item -> true;
+        TestEventsDeltaResponse secondPage = new TestEventsDeltaResponse();
+        secondPage.setValue(new LinkedList<TestEventItem>());
+        secondPage.setOdataDeltaLink("http://localhost/events?$skip=11");
+        int secondPageEventCount = 5;
+        for(int i = 0; i < secondPageEventCount; i++) {
+            TestEventItem testEventItem = new TestEventItem();
+            testEventItem.setSubject("Second Page Test Event: " + i);
+            secondPage.getValue().add(testEventItem);
+        }
+
+        AtomicInteger totalItemsProcessed = new AtomicInteger(0);
+
+        Function<TestEventItem, Boolean> processPageItemCallback = item -> {
+            totalItemsProcessed.incrementAndGet();
+            return true;
+        };
 
+        MockAdapter mockAdapter = new MockAdapter(mock(AuthenticationProvider.class), secondPage);
         PageIterator<TestEventItem, TestEventsDeltaResponse> pageIterator = new PageIterator.Builder<TestEventItem, TestEventsDeltaResponse>()
-            .client(baseClient)
+            .requestAdapter(mockAdapter)
             .collectionPage(originalPage)
             .collectionPageFactory(TestEventsDeltaResponse::createFromDiscriminatorValue)
             .processPageItemCallback(processPageItemCallback)
@@ -200,6 +216,7 @@ void given_CollectionPage_Delta_Link_Property_It_Iterates_Across_Pages() throws
 
         assertEquals(PageIterator.PageIteratorState.DELTA, pageIterator.getPageIteratorState());
         assertEquals("http://localhost/events?$skip=11", pageIterator.getDeltaLink());
+        assertEquals(inputEventCount + secondPageEventCount, totalItemsProcessed.get());
     }
 
     @Test

src/test/java/com/microsoft/graph/core/testModels/TestEventsDeltaResponse.java

@@ -8,22 +8,12 @@
 import java.util.*;
 import java.util.function.Consumer;
 
-public class TestEventsDeltaResponse implements Parsable, AdditionalDataHolder {
-    public Map<String, Object> additionalData;
+public class TestEventsDeltaResponse extends BaseCollectionPaginationCountResponse {
     private String odataDeltaLink;
-    private String odataNextLink;
     public List<TestEventItem> value;
 
     public TestEventsDeltaResponse() {
-        additionalData = new HashMap<>();
-    }
-
-    public Map<String, Object> getAdditionalData() {
-        return additionalData;
-    }
-
-    public void setAdditionalData(Map<String, Object> additionalData) {
-        this.additionalData = additionalData;
+        super();
     }
 
     public String getOdataDeltaLink() {
@@ -34,14 +24,6 @@ public void setOdataDeltaLink(String odataDeltaLink) {
         this.odataDeltaLink = odataDeltaLink;
     }
 
-    public String getOdataNextLink() {
-        return odataNextLink;
-    }
-
-    public void setOdataNextLink(String odataNextLink) {
-        this.odataNextLink = odataNextLink;
-    }
-
     public List<TestEventItem> getValue() {
         return value;
     }
@@ -51,22 +33,15 @@ public void setValue(List<TestEventItem> value) {
     }
 
     public Map<String, Consumer<ParseNode>> getFieldDeserializers() {
-        HashMap<String, Consumer<ParseNode>> fieldDeserializers = new HashMap<>();
-        fieldDeserializers.put("@odata.deltaLink", (n) -> setOdataDeltaLink(n.getStringValue()));
-        fieldDeserializers.put("@odata.nextLink", (n) -> setOdataNextLink(n.getStringValue()));
-        fieldDeserializers.put("value", (n) -> setValue(n.getCollectionOfObjectValues(TestEventItem::createFromDiscriminatorValue)));
-        return fieldDeserializers;
+        final HashMap<String, java.util.function.Consumer<ParseNode>> deserializerMap = new HashMap<String, java.util.function.Consumer<ParseNode>>(super.getFieldDeserializers());
+        deserializerMap.put("value", (n) -> { this.setValue(n.getCollectionOfObjectValues(TestEventItem::createFromDiscriminatorValue)); });
+        return deserializerMap;
     }
 
     public void serialize(SerializationWriter writer) {
-        if (writer == null) {
-            throw new IllegalArgumentException("writer");
-        }
-
-        writer.writeStringValue("@odata.deltaLink", odataDeltaLink);
-        writer.writeStringValue("@odata.nextLink", odataNextLink);
-        writer.writeCollectionOfObjectValues("value", value);
-        writer.writeAdditionalData(additionalData);
+        Objects.requireNonNull(writer);
+        super.serialize(writer);
+        writer.writeCollectionOfObjectValues("value", getValue());
     }
 
     public static TestEventsDeltaResponse createFromDiscriminatorValue(ParseNode parseNode) {