diff --git a/src/main/java/com/microsoft/graph/serializer/DerivedClassIdentifier.java b/src/main/java/com/microsoft/graph/serializer/DerivedClassIdentifier.java
index e01346a02..2d2fd1d8a 100644
--- a/src/main/java/com/microsoft/graph/serializer/DerivedClassIdentifier.java
+++ b/src/main/java/com/microsoft/graph/serializer/DerivedClassIdentifier.java
@@ -1,25 +1,32 @@
 package com.microsoft.graph.serializer;
 
+import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.CaseFormat;
 import com.google.gson.JsonObject;
 import com.microsoft.graph.logger.ILogger;
 
+import java.util.Locale;
 import java.util.Objects;
 import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
-/** This class provides methods to get the derived class corresponding to the OData type when deserializing payloads. */
+/**
+ * This class provides methods to get the derived class corresponding to the OData type when deserializing payloads.
+ */
 public class DerivedClassIdentifier {
 
     private final static String ODATA_TYPE_KEY = "@odata.type";
 
     private final ILogger logger;
+
     /**
      * Creates a new instance of the dereived class identifier.
+     *
      * @param logger The logger to use.
      */
     public DerivedClassIdentifier(@Nonnull ILogger logger) {
-        this.logger = Objects.requireNonNull(logger, "logger parameter cannot be null");;
+        this.logger = Objects.requireNonNull(logger, "logger parameter cannot be null");
+        ;
     }
 
     /**
@@ -29,7 +36,7 @@ public DerivedClassIdentifier(@Nonnull ILogger logger) {
      *
      * @param jsonObject  the raw JSON object of the response
      * @param parentClass the parent class the derived class should inherit from
-     * @return			the derived class if found, or null if not applicable
+     * @return the derived class if found, or null if not applicable
      */
     @Nullable
     public Class<?> identify(@Nonnull final JsonObject jsonObject, @Nullable final Class<?> parentClass) {
@@ -39,11 +46,7 @@ public Class<?> identify(@Nonnull final JsonObject jsonObject, @Nullable final C
             /** #microsoft.graph.user or #microsoft.graph.callrecords.callrecord */
             final String odataType = jsonObject.get(ODATA_TYPE_KEY).getAsString();
             final int lastDotIndex = odataType.lastIndexOf(".");
-            final String derivedType = (odataType.substring(0, lastDotIndex) +
-                ".models." +
-                CaseFormat.LOWER_CAMEL.to(CaseFormat.UPPER_CAMEL,
-                    odataType.substring(lastDotIndex + 1)))
-                .replace("#", "com.");
+            final String derivedType = oDataTypeToClassName(odataType);
             try {
                 Class<?> derivedClass = Class.forName(derivedType);
                 //Check that the derived class inherits from the given parent class
@@ -61,4 +64,20 @@ public Class<?> identify(@Nonnull final JsonObject jsonObject, @Nullable final C
         //If there is no defined OData type, return null
         return null;
     }
+
+    /**
+     * Convert {@code @odata.type} to proper java class name
+     *
+     * @param odataType to convert
+     * @return converted class name
+     */
+    @VisibleForTesting
+    static String oDataTypeToClassName(@Nonnull String odataType) {
+        Objects.requireNonNull(odataType);
+        final int lastDotIndex = odataType.lastIndexOf(".");
+        return (odataType.substring(0, lastDotIndex).toLowerCase(Locale.ROOT) +
+            ".models." +
+            CaseFormat.LOWER_CAMEL.to(CaseFormat.UPPER_CAMEL, odataType.substring(lastDotIndex + 1)))
+            .replace("#", "com.");
+    }
 }
diff --git a/src/test/java/com/microsoft/graph/serializer/DerivedClassIdentifierTest.java b/src/test/java/com/microsoft/graph/serializer/DerivedClassIdentifierTest.java
new file mode 100644
index 000000000..b73a29f25
--- /dev/null
+++ b/src/test/java/com/microsoft/graph/serializer/DerivedClassIdentifierTest.java
@@ -0,0 +1,18 @@
+package com.microsoft.graph.serializer;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+/**
+ * Created by Valentin Popov valentin@archiva.ru on 31.08.2021.
+ */
+class DerivedClassIdentifierTest {
+
+    @Test
+    void oDataTypeToClassName() {
+        Assertions.assertEquals("com.microsoft.graph.models.Message",
+            DerivedClassIdentifier.oDataTypeToClassName("#Microsoft.Graph.Message"));
+    }
+}