diff --git a/modules/openapi-generator/src/main/resources/dart2/api.mustache b/modules/openapi-generator/src/main/resources/dart2/api.mustache
index c6289c2b7662..439cbd99fde3 100644
--- a/modules/openapi-generator/src/main/resources/dart2/api.mustache
+++ b/modules/openapi-generator/src/main/resources/dart2/api.mustache
@@ -170,7 +170,7 @@ class {{{classname}}} {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
     {{#native_serialization}}
     {{#isArray}}
       final responseBody = await _decodeBodyBytes(response);
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/pet_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/pet_api.dart
index 68cb08b13e97..28b6cf30a31e 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/pet_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/pet_api.dart
@@ -67,7 +67,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Pet',) as Pet;
     
     }
@@ -186,7 +186,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       final responseBody = await _decodeBodyBytes(response);
       return (await apiClient.deserializeAsync(responseBody, 'List<Pet>') as List)
         .cast<Pet>()
@@ -249,7 +249,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       final responseBody = await _decodeBodyBytes(response);
       return (await apiClient.deserializeAsync(responseBody, 'List<Pet>') as List)
         .cast<Pet>()
@@ -311,7 +311,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Pet',) as Pet;
     
     }
@@ -369,7 +369,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Pet',) as Pet;
     
     }
@@ -523,7 +523,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'ApiResponse',) as ApiResponse;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/store_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/store_api.dart
index 3378d2f635af..225d048ce5a1 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/store_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/store_api.dart
@@ -108,7 +108,7 @@ class StoreApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return Map<String, int>.from(await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Map<String, int>'),);
 
     }
@@ -167,7 +167,7 @@ class StoreApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Order',) as Order;
     
     }
@@ -225,7 +225,7 @@ class StoreApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Order',) as Order;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/user_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/user_api.dart
index a44252a6130b..63754249a974 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/user_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib/lib/api/user_api.dart
@@ -269,7 +269,7 @@ class UserApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'User',) as User;
     
     }
@@ -336,7 +336,7 @@ class UserApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'String',) as String;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/another_fake_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/another_fake_api.dart
index 689eafbd8ed7..f08a617a5663 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/another_fake_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/another_fake_api.dart
@@ -67,7 +67,7 @@ class AnotherFakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'ModelClient',) as ModelClient;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/default_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/default_api.dart
index c62615343015..e29964f167d4 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/default_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/default_api.dart
@@ -50,7 +50,7 @@ class DefaultApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'FooGetDefaultResponse',) as FooGetDefaultResponse;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_api.dart
index 207fc6ddaf93..129b77709e50 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_api.dart
@@ -53,7 +53,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'FakeBigDecimalMap200Response',) as FakeBigDecimalMap200Response;
     
     }
@@ -97,7 +97,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'HealthCheckResult',) as HealthCheckResult;
     
     }
@@ -217,7 +217,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'bool',) as bool;
     
     }
@@ -271,7 +271,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'OuterComposite',) as OuterComposite;
     
     }
@@ -325,7 +325,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'num',) as num;
     
     }
@@ -379,7 +379,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'String',) as String;
     
     }
@@ -433,7 +433,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'OuterObjectWithEnumProperty',) as OuterObjectWithEnumProperty;
     
     }
@@ -676,7 +676,7 @@ class FakeApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'ModelClient',) as ModelClient;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_classname_tags123_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_classname_tags123_api.dart
index 2782357efb9b..96e70a27124e 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_classname_tags123_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/fake_classname_tags123_api.dart
@@ -67,7 +67,7 @@ class FakeClassnameTags123Api {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'ModelClient',) as ModelClient;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/pet_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/pet_api.dart
index 2f49efb4c3f1..e7bebd00a93a 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/pet_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/pet_api.dart
@@ -178,7 +178,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       final responseBody = await _decodeBodyBytes(response);
       return (await apiClient.deserializeAsync(responseBody, 'List<Pet>') as List)
         .cast<Pet>()
@@ -241,7 +241,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       final responseBody = await _decodeBodyBytes(response);
       return (await apiClient.deserializeAsync(responseBody, 'Set<Pet>') as List)
         .cast<Pet>()
@@ -303,7 +303,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Pet',) as Pet;
     
     }
@@ -507,7 +507,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'ApiResponse',) as ApiResponse;
     
     }
@@ -592,7 +592,7 @@ class PetApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'ApiResponse',) as ApiResponse;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/store_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/store_api.dart
index 1d666113cf72..1e8520dee320 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/store_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/store_api.dart
@@ -108,7 +108,7 @@ class StoreApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return Map<String, int>.from(await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Map<String, int>'),);
 
     }
@@ -167,7 +167,7 @@ class StoreApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Order',) as Order;
     
     }
@@ -225,7 +225,7 @@ class StoreApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'Order',) as Order;
     
     }
diff --git a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/user_api.dart b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/user_api.dart
index a44252a6130b..63754249a974 100644
--- a/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/user_api.dart
+++ b/samples/openapi3/client/petstore/dart2/petstore_client_lib_fake/lib/api/user_api.dart
@@ -269,7 +269,7 @@ class UserApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'User',) as User;
     
     }
@@ -336,7 +336,7 @@ class UserApi {
     // When a remote server returns no body with a status of 204, we shall not decode it.
     // At the time of writing this, `dart:convert` will throw an "Unexpected end of input"
     // FormatException when trying to decode an empty string.
-    if (response.body.isNotEmpty && response.statusCode != HttpStatus.noContent) {
+    if (response.bodyBytes.isNotEmpty && response.statusCode != HttpStatus.noContent) {
       return await apiClient.deserializeAsync(await _decodeBodyBytes(response), 'String',) as String;
     
     }