diff --git a/src/main/java/io/github/sashirestela/cleverclient/support/ReturnType.java b/src/main/java/io/github/sashirestela/cleverclient/support/ReturnType.java
index 30dbb9c..77736ec 100644
--- a/src/main/java/io/github/sashirestela/cleverclient/support/ReturnType.java
+++ b/src/main/java/io/github/sashirestela/cleverclient/support/ReturnType.java
@@ -56,22 +56,19 @@ private void setClassByEventIfExists(Method method) {
                         Arrays.stream(annotations)
                                 .map(a -> a.annotationType().getDeclaredAnnotation(StreamType.List.class).value())
                                 .findFirst()
-                                .get());
+                                .orElse(null));
             } else if (isAnnotationPresent(annotations, StreamType.class)) {
                 this.classByEvent = calculateClassByEvent(
                         new StreamType[] { Arrays.stream(annotations)
                                 .map(a -> a.annotationType().getDeclaredAnnotation(StreamType.class))
                                 .findFirst()
-                                .get() });
+                                .orElse(null) });
             }
         }
     }
 
     private boolean isAnnotationPresent(Annotation[] annotations, Class<? extends Annotation> clazz) {
-        return Arrays.stream(annotations)
-                .filter(a -> a.annotationType().isAnnotationPresent(clazz))
-                .findFirst()
-                .isPresent();
+        return Arrays.stream(annotations).anyMatch(a -> a.annotationType().isAnnotationPresent(clazz));
     }
 
     private Map<String, Class<?>> calculateClassByEvent(StreamType[] streamTypeList) {