diff --git a/src/main/java/com/microsoft/graph/serializer/DefaultSerializer.java b/src/main/java/com/microsoft/graph/serializer/DefaultSerializer.java
index 5b510482d..99c31906e 100644
--- a/src/main/java/com/microsoft/graph/serializer/DefaultSerializer.java
+++ b/src/main/java/com/microsoft/graph/serializer/DefaultSerializer.java
@@ -72,6 +72,11 @@ public DefaultSerializer(@Nonnull final ILogger logger) {
     /**
      * Creates a DefaultSerializer with an option to enable serializing of the null values.
      *
+     * Serializing of null values can have side effects on the service behavior.
+     * Sending null values in a PATCH request might reset existing values on the service side.
+     * Sending null values in a POST request might prevent the service from assigning default values to the properties.
+     * It is not recommended to send null values to the service in general and this setting should only be used when serializing information for a local store.
+     *
      * @param logger         the logger
      * @param serializeNulls the setting of whether or not to serialize the null values in the JSON object
      */
diff --git a/src/main/java/com/microsoft/graph/serializer/GsonFactory.java b/src/main/java/com/microsoft/graph/serializer/GsonFactory.java
index 645766f55..4b305e5ae 100644
--- a/src/main/java/com/microsoft/graph/serializer/GsonFactory.java
+++ b/src/main/java/com/microsoft/graph/serializer/GsonFactory.java
@@ -78,6 +78,11 @@ public static Gson getGsonInstance(@Nonnull final ILogger logger) {
     /**
      * Creates an instance of GSON
      *
+     * Serializing of null values can have side effects on the service behavior.
+     * Sending null values in a PATCH request might reset existing values on the service side.
+     * Sending null values in a POST request might prevent the service from assigning default values to the properties.
+     * It is not recommended to send null values to the service in general and this setting should only be used when serializing information for a local store.
+     *
      * @param logger         the logger
      * @param serializeNulls the setting of whether or not to serialize the null values in the JSON object
      * @return the new instance
diff --git a/src/test/java/com/microsoft/graph/http/CoreHttpProviderTests.java b/src/test/java/com/microsoft/graph/http/CoreHttpProviderTests.java
index ef5035482..43b8ebe76 100644
--- a/src/test/java/com/microsoft/graph/http/CoreHttpProviderTests.java
+++ b/src/test/java/com/microsoft/graph/http/CoreHttpProviderTests.java
@@ -56,13 +56,13 @@
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
-public class CoreHttpProviderTests {
+class CoreHttpProviderTests {
 
     private CoreHttpProvider mProvider;
     private Gson GSON = new GsonBuilder().create();
 
     @Test
-    public void testErrorResponse() throws Exception {
+    void testErrorResponse() throws Exception {
         final GraphErrorCodes expectedErrorCode = GraphErrorCodes.INVALID_REQUEST;
         final String expectedMessage = "Test error!";
         final GraphErrorResponse toSerialize = new GraphErrorResponse();
@@ -85,7 +85,7 @@ public void testErrorResponse() throws Exception {
     }
 
     @Test
-    public void testVerboseErrorResponse() throws Exception {
+    void testVerboseErrorResponse() throws Exception {
         final GraphErrorCodes expectedErrorCode = GraphErrorCodes.INVALID_REQUEST;
         final String expectedMessage = "Test error!";
         final GraphErrorResponse toSerialize = new GraphErrorResponse();
@@ -119,25 +119,25 @@ public void testVerboseErrorResponse() throws Exception {
     }
 
     @Test
-    public void testHasHeaderReturnsTrue() {
+    void testHasHeaderReturnsTrue() {
         HeaderOption h = new HeaderOption("name", "value");
         assertTrue(CoreHttpProvider.hasHeader(Arrays.asList(h), "name"));
     }
 
     @Test
-    public void testHasHeaderReturnsTrueWhenDifferentCase() {
+    void testHasHeaderReturnsTrueWhenDifferentCase() {
         HeaderOption h = new HeaderOption("name", "value");
         assertTrue(CoreHttpProvider.hasHeader(Arrays.asList(h), "NAME"));
     }
 
     @Test
-    public void testHasHeaderReturnsFalse() {
+    void testHasHeaderReturnsFalse() {
         HeaderOption h = new HeaderOption("name", "value");
         assertFalse(CoreHttpProvider.hasHeader(Arrays.asList(h), "blah"));
     }
 
     @Test
-    public void testStreamToStringReturnsData() {
+    void testStreamToStringReturnsData() {
         String data = GSON.toJson(Maps.newHashMap(
                 ImmutableMap.<String, String>builder()
                         .put("key", "value")
@@ -149,14 +149,14 @@ public void testStreamToStringReturnsData() {
     }
 
     @Test
-    public void testStreamToStringReturnsEmpty() {
+    void testStreamToStringReturnsEmpty() {
         final InputStream inputStream = new ByteArrayInputStream(new byte[0]);
 
         String convertedData = CoreHttpProvider.streamToString(inputStream);
         assertEquals("", convertedData);
     }
     @Test
-    public void emptyPostContentTypeIsNotReset() {
+    void emptyPostContentTypeIsNotReset() {
         final String contentTypeValue = "application/json";
         final HeaderOption ctype = new HeaderOption("Content-Type", contentTypeValue);
         final ArrayList<Option> options = new ArrayList<>();
@@ -173,7 +173,7 @@ public void emptyPostContentTypeIsNotReset() {
         assertEquals(contentTypeValue, request.body().contentType().toString());
     }
     @Test
-    public void emptyPostContentTypeIsNotSet() {
+    void emptyPostContentTypeIsNotSet() {
         final IHttpRequest absRequest = new BaseRequest<String>("https://localhost", mock(IBaseClient.class), Collections.emptyList(), String.class) {{
             this.setHttpMethod(HttpMethod.POST);
         }};
@@ -210,7 +210,7 @@ private void setCoreHttpProvider(final Object toSerialize) throws IOException {
                 mClient);
     }
     @Test
-    public void getHttpRequestDoesntSetRetryOrRedirectOptionsOnDefaultValues() throws MalformedURLException {
+    void getHttpRequestDoesntSetRetryOrRedirectOptionsOnDefaultValues() throws MalformedURLException {
         final IHttpRequest absRequest = mock(IHttpRequest.class);
         when(absRequest.getRequestUrl()).thenReturn(new URL("https://graph.microsoft.com/v1.0/me"));
         when(absRequest.getHttpMethod()).thenReturn(HttpMethod.GET);
@@ -239,7 +239,7 @@ public void getHttpRequestDoesntSetRetryOrRedirectOptionsOnDefaultValues() throw
     }
 
     @Test
-    public void getHttpRequestSetsRetryOrRedirectOptionsOnNonDefaultValues() throws MalformedURLException {
+    void getHttpRequestSetsRetryOrRedirectOptionsOnNonDefaultValues() throws MalformedURLException {
         final IHttpRequest absRequest = mock(IHttpRequest.class);
         when(absRequest.getRequestUrl()).thenReturn(new URL("https://graph.microsoft.com/v1.0/me"));
         when(absRequest.getHttpMethod()).thenReturn(HttpMethod.GET);
@@ -295,7 +295,7 @@ public void getHttpRequestSetsRetryOrRedirectOptionsOnNonDefaultValues() throws
     }
 
     @Test
-    public void getHttpRequestWithTextPlainBodyDoesNotSerializeAsJson() throws IOException {
+    void getHttpRequestWithTextPlainBodyDoesNotSerializeAsJson() throws IOException {
         final IHttpRequest absRequest = mock(IHttpRequest.class);
         when(absRequest.getRequestUrl()).thenReturn(new URL("https://graph.microsoft.com/v1.0/me"));
         when(absRequest.getHttpMethod()).thenReturn(HttpMethod.POST);
diff --git a/src/test/java/com/microsoft/graph/serializer/DefaultSerializerTest.java b/src/test/java/com/microsoft/graph/serializer/DefaultSerializerTest.java
index de269d613..26a84a48c 100644
--- a/src/test/java/com/microsoft/graph/serializer/DefaultSerializerTest.java
+++ b/src/test/java/com/microsoft/graph/serializer/DefaultSerializerTest.java
@@ -14,14 +14,14 @@
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.mock;
 
-public class DefaultSerializerTest {
+class DefaultSerializerTest {
 
     final ILogger logger = mock(ILogger.class);
     Gson gson = GsonFactory.getGsonInstance(logger);
     DefaultSerializer defaultSerializer = new DefaultSerializer(logger);
 
     @Test
-    public void testDeserializationOfObjectWithODataTypeProperty() {
+    void testDeserializationOfObjectWithODataTypeProperty() {
         // Given
         final String testJsonResponse =
             "{\"@odata.type\": \"#microsoft.graph.subReactionStub1\"}";
@@ -36,7 +36,7 @@ public void testDeserializationOfObjectWithODataTypeProperty() {
     }
 
     @Test
-    public void testDefaultSerializerDoesNotIncludeNullValuesByDefault() {
+    void testDefaultSerializerDoesNotIncludeNullValuesByDefault() {
         // Given
         final String testJsonResponse =
             "{\"@odata.type\": \"#microsoft.graph.messageStub\", \"body\": null}";
@@ -50,7 +50,7 @@ public void testDefaultSerializerDoesNotIncludeNullValuesByDefault() {
     }
 
     @Test
-    public void testDefaultNullSerializerDoesIncludeNullValues() {
+    void testDefaultNullSerializerDoesIncludeNullValues() {
         // Given
         final String testJsonResponse =
             "{\"@odata.type\": \"#microsoft.graph.messageStub\",\"body\":null}";