diff --git a/modules/openapi-generator/src/main/resources/dart2/api_client.mustache b/modules/openapi-generator/src/main/resources/dart2/api_client.mustache
index 9b83baf71dd..a3cd3c2463b 100644
--- a/modules/openapi-generator/src/main/resources/dart2/api_client.mustache
+++ b/modules/openapi-generator/src/main/resources/dart2/api_client.mustache
@@ -70,7 +70,7 @@ class ApiClient {
             }
           }
       }
-    } catch (e, stack) {
+    } on Exception catch (e, stack) {
       throw ApiException.withInner(500, 'Exception during deserialization.', e, stack);
     }
     throw ApiException(500, 'Could not find a suitable class for deserialization');
diff --git a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/pet_api.dart b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/pet_api.dart
index 0c625c2b04a..83af6ca8e62 100644
--- a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/pet_api.dart
+++ b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/pet_api.dart
@@ -41,7 +41,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -85,7 +86,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -265,7 +267,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -319,7 +322,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/store_api.dart b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/store_api.dart
index 5f88bf5ac99..3fc1364a102 100644
--- a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/store_api.dart
+++ b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/store_api.dart
@@ -43,7 +43,8 @@ class StoreApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/user_api.dart b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/user_api.dart
index 94b245a5609..52202df0ea4 100644
--- a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/user_api.dart
+++ b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api/user_api.dart
@@ -41,7 +41,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -82,7 +83,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -123,7 +125,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -166,7 +169,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -299,7 +303,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -345,7 +350,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api_client.dart b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api_client.dart
index 016e939e55d..d0db1fd65ec 100644
--- a/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api_client.dart
+++ b/samples/client/petstore/dart2/flutter_petstore/openapi/lib/api_client.dart
@@ -65,7 +65,7 @@ class ApiClient {
             }
           }
       }
-    } catch (e, stack) {
+    } on Exception catch (e, stack) {
       throw ApiException.withInner(
           500, 'Exception during deserialization.', e, stack);
     }
diff --git a/samples/client/petstore/dart2/openapi-browser-client/lib/api/pet_api.dart b/samples/client/petstore/dart2/openapi-browser-client/lib/api/pet_api.dart
index 0c625c2b04a..83af6ca8e62 100644
--- a/samples/client/petstore/dart2/openapi-browser-client/lib/api/pet_api.dart
+++ b/samples/client/petstore/dart2/openapi-browser-client/lib/api/pet_api.dart
@@ -41,7 +41,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -85,7 +86,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -265,7 +267,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -319,7 +322,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/openapi-browser-client/lib/api/store_api.dart b/samples/client/petstore/dart2/openapi-browser-client/lib/api/store_api.dart
index 5f88bf5ac99..3fc1364a102 100644
--- a/samples/client/petstore/dart2/openapi-browser-client/lib/api/store_api.dart
+++ b/samples/client/petstore/dart2/openapi-browser-client/lib/api/store_api.dart
@@ -43,7 +43,8 @@ class StoreApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/openapi-browser-client/lib/api/user_api.dart b/samples/client/petstore/dart2/openapi-browser-client/lib/api/user_api.dart
index 94b245a5609..52202df0ea4 100644
--- a/samples/client/petstore/dart2/openapi-browser-client/lib/api/user_api.dart
+++ b/samples/client/petstore/dart2/openapi-browser-client/lib/api/user_api.dart
@@ -41,7 +41,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -82,7 +83,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -123,7 +125,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -166,7 +169,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -299,7 +303,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -345,7 +350,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/openapi-browser-client/lib/api_client.dart b/samples/client/petstore/dart2/openapi-browser-client/lib/api_client.dart
index 72a7c0f345b..acf873a63b2 100644
--- a/samples/client/petstore/dart2/openapi-browser-client/lib/api_client.dart
+++ b/samples/client/petstore/dart2/openapi-browser-client/lib/api_client.dart
@@ -65,7 +65,7 @@ class ApiClient {
             }
           }
       }
-    } catch (e, stack) {
+    } on Exception catch (e, stack) {
       throw ApiException.withInner(
           500, 'Exception during deserialization.', e, stack);
     }
diff --git a/samples/client/petstore/dart2/openapi/lib/api/pet_api.dart b/samples/client/petstore/dart2/openapi/lib/api/pet_api.dart
index 0c625c2b04a..83af6ca8e62 100644
--- a/samples/client/petstore/dart2/openapi/lib/api/pet_api.dart
+++ b/samples/client/petstore/dart2/openapi/lib/api/pet_api.dart
@@ -41,7 +41,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -85,7 +86,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -265,7 +267,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -319,7 +322,8 @@ class PetApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/openapi/lib/api/store_api.dart b/samples/client/petstore/dart2/openapi/lib/api/store_api.dart
index 5f88bf5ac99..3fc1364a102 100644
--- a/samples/client/petstore/dart2/openapi/lib/api/store_api.dart
+++ b/samples/client/petstore/dart2/openapi/lib/api/store_api.dart
@@ -43,7 +43,8 @@ class StoreApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/openapi/lib/api/user_api.dart b/samples/client/petstore/dart2/openapi/lib/api/user_api.dart
index 94b245a5609..52202df0ea4 100644
--- a/samples/client/petstore/dart2/openapi/lib/api/user_api.dart
+++ b/samples/client/petstore/dart2/openapi/lib/api/user_api.dart
@@ -41,7 +41,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -82,7 +83,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -123,7 +125,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -166,7 +169,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -299,7 +303,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
@@ -345,7 +350,8 @@ class UserApi {
 
     if (response.statusCode >= 400) {
       throw new ApiException(response.statusCode, response.body);
-    } else if (response.body != null) {} else {
+    } else if (response.body != null) {
+    } else {
       return;
     }
   }
diff --git a/samples/client/petstore/dart2/openapi/lib/api_client.dart b/samples/client/petstore/dart2/openapi/lib/api_client.dart
index 016e939e55d..d0db1fd65ec 100644
--- a/samples/client/petstore/dart2/openapi/lib/api_client.dart
+++ b/samples/client/petstore/dart2/openapi/lib/api_client.dart
@@ -65,7 +65,7 @@ class ApiClient {
             }
           }
       }
-    } catch (e, stack) {
+    } on Exception catch (e, stack) {
       throw ApiException.withInner(
           500, 'Exception during deserialization.', e, stack);
     }