diff --git a/modules/openapi-generator/pom.xml b/modules/openapi-generator/pom.xml
index 7e793f45499..9ab17b45b53 100644
--- a/modules/openapi-generator/pom.xml
+++ b/modules/openapi-generator/pom.xml
@@ -198,8 +198,8 @@
         <diffutils-version>1.3.0</diffutils-version>
         <guava-version>26.0-jre</guava-version>
         <generex-version>1.0.2</generex-version>
-        <jackson-version>2.9.10</jackson-version>
-        <jackson-threetenbp-version>2.9.10</jackson-threetenbp-version>
+        <jackson-version>2.10.1</jackson-version>
+        <jackson-threetenbp-version>2.10.0</jackson-threetenbp-version>
         <kotlin-version>1.3.60</kotlin-version>
     </properties>
     <dependencies>
@@ -212,7 +212,7 @@
             <groupId>${swagger-parser-groupid}</groupId>
             <artifactId>swagger-parser</artifactId>
             <version>${swagger-parser-version}</version>
-        </dependency> 
+        </dependency>
         <dependency>
             <groupId>com.samskivert</groupId>
             <artifactId>jmustache</artifactId>
@@ -268,6 +268,11 @@
             <artifactId>jackson-datatype-guava</artifactId>
             <version>${jackson-version}</version>
         </dependency>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-core</artifactId>
+            <version>${jackson-version}</version>
+        </dependency>
         <dependency>
             <groupId>org.testng</groupId>
             <artifactId>testng</artifactId>
diff --git a/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/JsonCacheImpl.java b/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/JsonCacheImpl.java
index 9409372b4d4..3f2688fc5e0 100644
--- a/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/JsonCacheImpl.java
+++ b/modules/openapi-generator/src/main/java/org/openapitools/codegen/utils/JsonCacheImpl.java
@@ -1364,7 +1364,11 @@ class JsonCacheImpl implements JsonCache.Root {
         } else {
             JsonNode node = root.at(ptr);
             Object value = node.isPojo() && !JsonNode.class.isAssignableFrom(type) ? ((POJONode) node).getPojo() : node;
-            result = mapper.convertValue(value, type);
+            if ((value != null) && (value.getClass() == type)) {
+                result = (T) value;
+            } else {
+                result = mapper.convertValue(value, type);
+            }
         }
         return result;
     }
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/serializer/SerializerUtilsTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/serializer/SerializerUtilsTest.java
index 80629f717bd..046645ec0db 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/serializer/SerializerUtilsTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/serializer/SerializerUtilsTest.java
@@ -52,7 +52,7 @@ public class SerializerUtilsTest {
                "      description: Some description\n" +
                "      operationId: pingOp\n" +
                "      responses:\n" +
-               "        200:\n" +
+               "        \"200\":\n" +
                "          description: Ok\n" +
                "components:\n" +
                "  schemas:\n" +
@@ -178,7 +178,7 @@ public class SerializerUtilsTest {
                 "      description: Some description\n" +
                 "      operationId: pingOp\n" +
                 "      responses:\n" +
-                "        200:\n" +
+                "        \"200\":\n" +
                 "          description: Ok\n"; 
         assertEquals(content, expected);
     }
diff --git a/pom.xml b/pom.xml
index b370f12d3db..5ff033ed37a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1401,9 +1401,9 @@
     <properties>
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
-        <swagger-core-version>2.0.10</swagger-core-version>
+        <swagger-core-version>2.1.1</swagger-core-version>
         <swagger-parser-groupid>io.swagger.parser.v3</swagger-parser-groupid>
-        <swagger-parser-version>2.0.16</swagger-parser-version>
+        <swagger-parser-version>2.0.17</swagger-parser-version>
         <scala-version>2.11.1</scala-version>
         <felix-version>3.3.1</felix-version>
         <commons-io-version>2.4</commons-io-version>