diff --git a/samples/client/petstore/java/feign-no-nullable/src/main/java/org/openapitools/client/ApiResponseDecoder.java b/samples/client/petstore/java/feign-no-nullable/src/main/java/org/openapitools/client/ApiResponseDecoder.java
index d74d1d8768d..659cad2102c 100644
--- a/samples/client/petstore/java/feign-no-nullable/src/main/java/org/openapitools/client/ApiResponseDecoder.java
+++ b/samples/client/petstore/java/feign-no-nullable/src/main/java/org/openapitools/client/ApiResponseDecoder.java
@@ -25,7 +25,7 @@ public class ApiResponseDecoder extends JacksonDecoder {
     Map<String, Collection<String>> responseHeaders = Collections.unmodifiableMap(response.headers());
         //Detects if the type is an instance of the parameterized class ApiResponse
         Type responseBodyType;
-        if (Types.getRawType(type).isAssignableFrom(ApiResponse.class)) {
+        if (type instanceof ParameterizedType && Types.getRawType(type).isAssignableFrom(ApiResponse.class)) {
             //The ApiResponse class has a single type parameter, the Dto class itself
             responseBodyType = ((ParameterizedType) type).getActualTypeArguments()[0];
             Object body = super.decode(response, responseBodyType);
@@ -35,4 +35,4 @@ public class ApiResponseDecoder extends JacksonDecoder {
             return super.decode(response, type);
         }
     }
-}
\ No newline at end of file
+}
diff --git a/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/ApiResponseDecoder.java b/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/ApiResponseDecoder.java
index d74d1d8768d..659cad2102c 100644
--- a/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/ApiResponseDecoder.java
+++ b/samples/client/petstore/java/feign/src/main/java/org/openapitools/client/ApiResponseDecoder.java
@@ -25,7 +25,7 @@ public class ApiResponseDecoder extends JacksonDecoder {
     Map<String, Collection<String>> responseHeaders = Collections.unmodifiableMap(response.headers());
         //Detects if the type is an instance of the parameterized class ApiResponse
         Type responseBodyType;
-        if (Types.getRawType(type).isAssignableFrom(ApiResponse.class)) {
+        if (type instanceof ParameterizedType && Types.getRawType(type).isAssignableFrom(ApiResponse.class)) {
             //The ApiResponse class has a single type parameter, the Dto class itself
             responseBodyType = ((ParameterizedType) type).getActualTypeArguments()[0];
             Object body = super.decode(response, responseBodyType);
@@ -35,4 +35,4 @@ public class ApiResponseDecoder extends JacksonDecoder {
             return super.decode(response, type);
         }
     }
-}
\ No newline at end of file
+}