diff --git a/README.md b/README.md
index 08d16048eff..b50afb52365 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@
 [![Stable releases in Maven Central](https://img.shields.io/maven-metadata/v/https/repo1.maven.org/maven2/org/openapitools/openapi-generator/maven-metadata.xml.svg)](http://search.maven.org/#search%7Cgav%7C1%7Cg%3A%22org.openapitools%22%20AND%20a%3A%22openapi-generator%22)
 [![Apache 2.0 License](https://img.shields.io/badge/License-Apache%202.0-orange)](./LICENSE)
 [![Open Collective backers](https://img.shields.io/opencollective/backers/openapi_generator?color=orange&label=OpenCollective%20Backers)](https://opencollective.com/openapi_generator)
-[![Join the Slack chat room](https://img.shields.io/badge/Slack-Join%20the%20chat%20room-orange)](https://join.slack.com/t/openapi-generator/shared_invite/zt-2uoef5v0g-XGwo8~2oJ3EoziDSO1CmdQ)
+[![Join the Slack chat room](https://img.shields.io/badge/Slack-Join%20the%20chat%20room-orange)](https://join.slack.com/t/openapi-generator/shared_invite/zt-2wmkn4s8g-n19PJ99Y6Vei74WMUIehQA)
 [![Follow OpenAPI Generator Twitter account to get the latest update](https://img.shields.io/twitter/follow/oas_generator.svg?style=social&label=Follow)](https://twitter.com/oas_generator)
 [![Contribute with Gitpod](https://img.shields.io/badge/Contribute%20with-Gitpod-908a85?logo=gitpod)](https://gitpod.io/#https://github.com/OpenAPITools/openapi-generator)
 [![Conan Center](https://shields.io/conan/v/openapi-generator)](https://conan.io/center/recipes/openapi-generator)
diff --git a/docs/faq.md b/docs/faq.md
index 9b416e374d5..061135a68b5 100644
--- a/docs/faq.md
+++ b/docs/faq.md
@@ -5,7 +5,7 @@ title: "FAQ: General"
 
 ## Do you have a chat room?
 
-[![Join the Slack chat room](https://img.shields.io/badge/Slack-Join%20the%20chat%20room-orange)](https://join.slack.com/t/openapi-generator/shared_invite/zt-2uoef5v0g-XGwo8~2oJ3EoziDSO1CmdQ)
+[![Join the Slack chat room](https://img.shields.io/badge/Slack-Join%20the%20chat%20room-orange)](https://join.slack.com/t/openapi-generator/shared_invite/zt-2wmkn4s8g-n19PJ99Y6Vei74WMUIehQA)
 
 ## What is the governance structure of the OpenAPI Generator project?
 
diff --git a/modules/openapi-generator/src/main/resources/Java/libraries/native/api.mustache b/modules/openapi-generator/src/main/resources/Java/libraries/native/api.mustache
index 0ade8e9c2ba..309ee2fc321 100644
--- a/modules/openapi-generator/src/main/resources/Java/libraries/native/api.mustache
+++ b/modules/openapi-generator/src/main/resources/Java/libraries/native/api.mustache
@@ -271,22 +271,46 @@ public class {{classname}} {
         }
         {{/vendorExtensions.x-java-text-plain-string}}
         {{^vendorExtensions.x-java-text-plain-string}}
-        return new ApiResponse<{{{returnType}}}{{^returnType}}Void{{/returnType}}>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          {{#returnType}}
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<{{{returnType}}}>() {}) // closes the InputStream
-          {{/returnType}}
-          {{^returnType}}
-          null
-          {{/returnType}}
+        {{#returnType}}
+        {{! Fix for https://github.com/OpenAPITools/openapi-generator/issues/13968 }}
+        {{! This part had a bugfix for an empty response in the past, but this part of that PR was reverted because it was not doing anything. }}
+        {{! Keep this documentation here, because the problem is not obvious. }}
+        {{! `InputStream.available()` was used, but that only works for inputstreams that are already in memory, it will not give the right result if it is a remote stream. We only work with remote streams here. }}
+        {{! https://github.com/OpenAPITools/openapi-generator/pull/13993/commits/3e!37411d2acef0311c82e6d941a8e40b3bc0b6da }}
+        {{! The `available` method would work with a `PushbackInputStream`, because we could read 1 byte to check if it exists then push it back so Jackson can read it again. The issue with that is that it will also insert an ascii character for "head of input" and that will break Jackson as it does not handle special whitespace characters. }}
+        {{! A fix for that problem is to read it into a string and remove those characters, but if we need to read it before giving it to jackson to fix the string then just reading it into a string as is to do an emptiness check is the cleaner solution. }}
+        {{! We could also manipulate the inputstream to remove that bad character, but string manipulation is easier to read and this codepath is not asyncronus so we do not gain anything by reading the stream later. }}
+        {{! This fix does make it unsuitable for large amounts of data because `InputStream.readAllbytes` is not meant for it, but a syncronus client is already not the right tool for that.}}
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<{{{returnType}}}>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
+        return new ApiResponse<{{{returnType}}}>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<{{{returnType}}}>() {})
         );
+        {{/returnType}}
+        {{^returnType}}
+        return new ApiResponse<{{{returnType}}}>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
+        );
+        {{/returnType}}
         {{/vendorExtensions.x-java-text-plain-string}}
       } finally {
         {{^returnType}}
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
         {{/returnType}}
diff --git a/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/JavaClientCodegenTest.java b/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/JavaClientCodegenTest.java
index dc31a2f42a1..f050ffe7877 100644
--- a/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/JavaClientCodegenTest.java
+++ b/modules/openapi-generator/src/test/java/org/openapitools/codegen/java/JavaClientCodegenTest.java
@@ -3263,4 +3263,73 @@ public class JavaClientCodegenTest {
                 " getCall(Integer queryParameter, final ApiCallback _callback)"
         );
     }
+
+    @Test
+    public void callNativeServiceWithEmptyResponseSync() throws IOException {
+        Map<String, Object> properties = new HashMap<>();
+        properties.put(CodegenConstants.API_PACKAGE, "xyz.abcdef.api");
+        properties.put("asyncNative", "false");
+
+        File output = Files.createTempDirectory("test").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = new CodegenConfigurator()
+                .setGeneratorName("java")
+                .setLibrary(JavaClientCodegen.NATIVE)
+                .setAdditionalProperties(properties)
+                .setInputSpec("src/test/resources/3_0/java/native/issue13968.yaml")
+                .setOutputDir(output.getAbsolutePath().replace("\\", "/"));
+
+        final ClientOptInput clientOptInput = configurator.toClientOptInput();
+        DefaultGenerator generator = new DefaultGenerator();
+
+        Map<String, File> files = generator.opts(clientOptInput).generate().stream()
+                .collect(Collectors.toMap(File::getName, Function.identity()));
+
+        File apiFile = files.get("DefaultApi.java");
+        assertNotNull(apiFile);
+
+        JavaFileAssert.assertThat(apiFile).fileContains(
+                //reading the body into a string, then checking if it is blank.
+                "String responseBody = new String(localVarResponse.body().readAllBytes());",
+                "responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<LocationData>() {})"
+        );
+    }
+
+
+    /**
+     * This checks that the async client is not affected by this fix.
+     * See https://github.com/OpenAPITools/openapi-generator/issues/13968
+     */
+    @Test
+    public void callNativeServiceWithEmptyResponseAsync() throws IOException {
+        Map<String, Object> properties = new HashMap<>();
+        properties.put(CodegenConstants.API_PACKAGE, "xyz.abcdef.api");
+        properties.put("asyncNative", "true");
+
+        File output = Files.createTempDirectory("test").toFile();
+        output.deleteOnExit();
+
+        final CodegenConfigurator configurator = new CodegenConfigurator()
+                .setGeneratorName("java")
+                .setLibrary(JavaClientCodegen.NATIVE)
+                .setAdditionalProperties(properties)
+                .setInputSpec("src/test/resources/3_0/java/native/issue13968.yaml")
+                .setOutputDir(output.getAbsolutePath().replace("\\", "/"));
+
+        final ClientOptInput clientOptInput = configurator.toClientOptInput();
+        DefaultGenerator generator = new DefaultGenerator();
+
+        Map<String, File> files = generator.opts(clientOptInput).generate().stream()
+                .collect(Collectors.toMap(File::getName, Function.identity()));
+
+        File apiFile = files.get("DefaultApi.java");
+        assertNotNull(apiFile);
+
+        JavaFileAssert.assertThat(apiFile).fileDoesNotContain(
+                //reading the body into a string, then checking if it is blank.
+                "String responseBody = new String(localVarResponse.body().readAllBytes());",
+                "responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<LocationData>() {})"
+        );
+    }
 }
\ No newline at end of file
diff --git a/modules/openapi-generator/src/test/resources/3_0/java/native/issue13968.yaml b/modules/openapi-generator/src/test/resources/3_0/java/native/issue13968.yaml
new file mode 100644
index 00000000000..e44e500d5d2
--- /dev/null
+++ b/modules/openapi-generator/src/test/resources/3_0/java/native/issue13968.yaml
@@ -0,0 +1,33 @@
+openapi: 3.0.3
+info:
+  title: Example Hello API
+  description: ''
+  version: v1
+servers:
+  - url: http://localhost
+    description: Global Endpoint
+paths:
+  /v1/emptyResponse:
+    get:
+      operationId: empty
+      description: returns an empty response
+      responses:
+        200:
+          description: Successful operation
+          content:
+            application/json:
+              schema:
+                $ref: '#/components/schemas/LocationData'
+        204:
+          description: Empty response
+components:
+  schemas:
+    LocationData:
+      type: object
+      properties:
+        xPos:
+          type: integer
+          format: int32
+        yPos:
+          type: integer
+          format: int32
diff --git a/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/api/BodyApi.java b/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/api/BodyApi.java
index 257a7a54506..850a0067f4b 100644
--- a/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/api/BodyApi.java
+++ b/samples/client/echo_api/java/native/src/main/java/org/openapitools/client/api/BodyApi.java
@@ -120,10 +120,21 @@ public class BodyApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testBinaryGif", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<File>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<File>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<File>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<File>() {})
         );
       } finally {
       }
@@ -494,10 +505,21 @@ public class BodyApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testEchoBodyAllOfPet", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Pet>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Pet>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Pet>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Pet>() {})
         );
       } finally {
       }
@@ -650,10 +672,21 @@ public class BodyApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testEchoBodyPet", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Pet>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Pet>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Pet>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Pet>() {})
         );
       } finally {
       }
@@ -806,10 +839,21 @@ public class BodyApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testEchoBodyStringEnum", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<StringEnumRef>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<StringEnumRef>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<StringEnumRef>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<StringEnumRef>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/PetApi.java b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/PetApi.java
index 8a29cf444b0..d8e77055b86 100644
--- a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/PetApi.java
+++ b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/PetApi.java
@@ -121,10 +121,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("addPet", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Pet>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Pet>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Pet>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Pet>() {})
         );
       } finally {
       }
@@ -199,15 +210,15 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("deletePet", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -280,10 +291,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("findPetsByStatus", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<List<Pet>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<List<Pet>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<List<Pet>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<List<Pet>>() {})
         );
       } finally {
       }
@@ -371,10 +393,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("findPetsByTags", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<List<Pet>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<List<Pet>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<List<Pet>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<List<Pet>>() {})
         );
       } finally {
       }
@@ -458,10 +491,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getPetById", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Pet>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Pet>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Pet>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Pet>() {})
         );
       } finally {
       }
@@ -535,10 +579,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("updatePet", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Pet>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Pet>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Pet>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Pet>() {})
         );
       } finally {
       }
@@ -615,15 +670,15 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("updatePetWithForm", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -714,10 +769,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("uploadFile", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<ModelApiResponse>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<ModelApiResponse>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<ModelApiResponse>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<ModelApiResponse>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/StoreApi.java b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/StoreApi.java
index 40fd9c15c9e..69dda1a1214 100644
--- a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/StoreApi.java
+++ b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/StoreApi.java
@@ -117,15 +117,15 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("deleteOrder", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -193,10 +193,21 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getInventory", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Map<String, Integer>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Map<String, Integer>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Map<String, Integer>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Map<String, Integer>>() {})
         );
       } finally {
       }
@@ -261,10 +272,21 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getOrderById", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Order>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Order>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Order>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Order>() {})
         );
       } finally {
       }
@@ -334,10 +356,21 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("placeOrder", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Order>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Order>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Order>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Order>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/UserApi.java b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/UserApi.java
index da390054dcd..e8030ff7aa4 100644
--- a/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/UserApi.java
+++ b/samples/client/petstore/java/native-jakarta/src/main/java/org/openapitools/client/api/UserApi.java
@@ -118,15 +118,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("createUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -199,15 +199,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("createUsersWithArrayInput", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -280,15 +280,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("createUsersWithListInput", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -361,15 +361,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("deleteUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -439,10 +439,21 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getUserByName", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<User>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<User>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<User>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<User>() {})
         );
       } finally {
       }
@@ -514,10 +525,21 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("loginUser", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<String>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<String>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<String>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<String>() {})
         );
       } finally {
       }
@@ -603,15 +625,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("logoutUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -676,15 +698,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("updateUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/AnotherFakeApi.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/AnotherFakeApi.java
index b1b630cd510..f8e8956e4ea 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/AnotherFakeApi.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/AnotherFakeApi.java
@@ -113,10 +113,21 @@ public class AnotherFakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("call123testSpecialTags", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Client>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Client>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Client>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Client>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/DefaultApi.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/DefaultApi.java
index e89ac1df463..96341736067 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/DefaultApi.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/DefaultApi.java
@@ -111,10 +111,21 @@ public class DefaultApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fooGet", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<FooGetDefaultResponse>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<FooGetDefaultResponse>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<FooGetDefaultResponse>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<FooGetDefaultResponse>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeApi.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeApi.java
index a4986f04291..0de6a99e318 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeApi.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeApi.java
@@ -128,10 +128,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fakeBigDecimalMap", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<FakeBigDecimalMap200Response>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<FakeBigDecimalMap200Response>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<FakeBigDecimalMap200Response>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<FakeBigDecimalMap200Response>() {})
         );
       } finally {
       }
@@ -194,10 +205,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fakeHealthGet", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<HealthCheckResult>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<HealthCheckResult>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<HealthCheckResult>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<HealthCheckResult>() {})
         );
       } finally {
       }
@@ -262,10 +284,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fakeOuterBooleanSerialize", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Boolean>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Boolean>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Boolean>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Boolean>() {})
         );
       } finally {
       }
@@ -336,10 +369,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fakeOuterCompositeSerialize", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<OuterComposite>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<OuterComposite>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<OuterComposite>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<OuterComposite>() {})
         );
       } finally {
       }
@@ -410,10 +454,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fakeOuterNumberSerialize", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<BigDecimal>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<BigDecimal>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<BigDecimal>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<BigDecimal>() {})
         );
       } finally {
       }
@@ -484,10 +539,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("fakeOuterStringSerialize", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<String>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<String>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<String>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<String>() {})
         );
       } finally {
       }
@@ -551,10 +617,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getApplicationJsonUtf8", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<List<OuterEnum>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<List<OuterEnum>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<List<OuterEnum>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<List<OuterEnum>>() {})
         );
       } finally {
       }
@@ -617,10 +694,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getArrayOfEnums", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<List<OuterEnum>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<List<OuterEnum>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<List<OuterEnum>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<List<OuterEnum>>() {})
         );
       } finally {
       }
@@ -683,15 +771,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testAdditionalPropertiesReference", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -764,15 +852,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testBodyWithFileSchema", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -847,15 +935,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testBodyWithQueryParams", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -949,10 +1037,21 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testClientModel", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Client>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Client>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Client>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Client>() {})
         );
       } finally {
       }
@@ -1051,15 +1150,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testEndpointParameters", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1205,15 +1304,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testEnumParameters", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1365,15 +1464,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testGroupParameters", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1552,15 +1651,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testInlineAdditionalProperties", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1633,15 +1732,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testInlineFreeformAdditionalProperties", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1716,15 +1815,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testJsonFormData", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1820,15 +1919,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testQueryParameterCollectionFormat", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -1934,15 +2033,15 @@ public class FakeApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testStringMapReference", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeClassnameTags123Api.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeClassnameTags123Api.java
index 027d90cdd94..43f1a867c6d 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeClassnameTags123Api.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/FakeClassnameTags123Api.java
@@ -119,10 +119,21 @@ public class FakeClassnameTags123Api {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("testClassname", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Client>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Client>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Client>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Client>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/PetApi.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/PetApi.java
index 63bb5d85db8..24c7123889d 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/PetApi.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/PetApi.java
@@ -119,15 +119,15 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("addPet", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -202,15 +202,15 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("deletePet", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -283,10 +283,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("findPetsByStatus", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<List<Pet>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<List<Pet>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<List<Pet>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<List<Pet>>() {})
         );
       } finally {
       }
@@ -374,10 +385,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("findPetsByTags", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<List<Pet>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<List<Pet>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<List<Pet>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<List<Pet>>() {})
         );
       } finally {
       }
@@ -461,10 +483,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getPetById", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Pet>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Pet>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Pet>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Pet>() {})
         );
       } finally {
       }
@@ -532,15 +565,15 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("updatePet", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -617,15 +650,15 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("updatePetWithForm", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -716,10 +749,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("uploadFile", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<ModelApiResponse>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<ModelApiResponse>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<ModelApiResponse>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<ModelApiResponse>() {})
         );
       } finally {
       }
@@ -827,10 +871,21 @@ public class PetApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("uploadFileWithRequiredFile", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<ModelApiResponse>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<ModelApiResponse>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<ModelApiResponse>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<ModelApiResponse>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/StoreApi.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/StoreApi.java
index 4f97d8761d3..3300e0a41d8 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/StoreApi.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/StoreApi.java
@@ -117,15 +117,15 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("deleteOrder", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -193,10 +193,21 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getInventory", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Map<String, Integer>>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Map<String, Integer>>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Map<String, Integer>>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Map<String, Integer>>() {})
         );
       } finally {
       }
@@ -261,10 +272,21 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getOrderById", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Order>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Order>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Order>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Order>() {})
         );
       } finally {
       }
@@ -334,10 +356,21 @@ public class StoreApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("placeOrder", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<Order>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<Order>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<Order>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<Order>() {})
         );
       } finally {
       }
diff --git a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/UserApi.java b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/UserApi.java
index 239f2753a8e..9422119d52e 100644
--- a/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/UserApi.java
+++ b/samples/client/petstore/java/native/src/main/java/org/openapitools/client/api/UserApi.java
@@ -118,15 +118,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("createUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -199,15 +199,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("createUsersWithArrayInput", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -280,15 +280,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("createUsersWithListInput", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -361,15 +361,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("deleteUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -439,10 +439,21 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("getUserByName", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<User>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<User>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<User>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<User>() {})
         );
       } finally {
       }
@@ -514,10 +525,21 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("loginUser", localVarResponse);
         }
+        if (localVarResponse.body() == null) {
+          return new ApiResponse<String>(
+              localVarResponse.statusCode(),
+              localVarResponse.headers().map(),
+              null
+          );
+        }
+
+        String responseBody = new String(localVarResponse.body().readAllBytes());
+        localVarResponse.body().close();
+
         return new ApiResponse<String>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          localVarResponse.body() == null ? null : memberVarObjectMapper.readValue(localVarResponse.body(), new TypeReference<String>() {}) // closes the InputStream
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            responseBody.isBlank()? null: memberVarObjectMapper.readValue(responseBody, new TypeReference<String>() {})
         );
       } finally {
       }
@@ -603,15 +625,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("logoutUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
@@ -676,15 +698,15 @@ public class UserApi {
         if (localVarResponse.statusCode()/ 100 != 2) {
           throw getApiException("updateUser", localVarResponse);
         }
-        return new ApiResponse<Void>(
-          localVarResponse.statusCode(),
-          localVarResponse.headers().map(),
-          null
+        return new ApiResponse<>(
+            localVarResponse.statusCode(),
+            localVarResponse.headers().map(),
+            null
         );
       } finally {
         // Drain the InputStream
         while (localVarResponse.body().read() != -1) {
-            // Ignore
+          // Ignore
         }
         localVarResponse.body().close();
       }
diff --git a/website/src/pages/index.js b/website/src/pages/index.js
index 630820806ae..d29b80c2813 100755
--- a/website/src/pages/index.js
+++ b/website/src/pages/index.js
@@ -120,7 +120,7 @@ const callouts = [
                 </p>
                 <p>Slack is free to <a href="https://slack.com/downloads" className="href">download</a>, and our
                     workspace is free to <a
-                        href="https://join.slack.com/t/openapi-generator/shared_invite/zt-2uoef5v0g-XGwo8~2oJ3EoziDSO1CmdQ"
+                        href="https://join.slack.com/t/openapi-generator/shared_invite/zt-2wmkn4s8g-n19PJ99Y6Vei74WMUIehQA"
                         className="href">sign up</a>.
                 </p>
             </>