@@ -1,7 +1,7 @@
 /*
- * Copyright (c) 2008-2021 Jonathan Schleifer <js@nil.im>
+ * Copyright (c) 2008-2022 Jonathan Schleifer <js@nil.im>
  *
  * All rights reserved.
  *
  * This file is part of ObjFW. It may be distributed under the terms of the
  * Q Public License 1.0, which can be found in the file LICENSE.QPL included in
@@ -36,13 +36,11 @@
 @property (readonly, nonatomic) SEL selector;
 
 /**
  * @brief The object which does not (fully) implement the selector.
  */
-@property (readonly, nonatomic) id object;
-
-+ (instancetype)exception OF_UNAVAILABLE;
+@property OF_NULLABLE_PROPERTY (readonly, nonatomic) id object;
 
 /**
  * @brief Creates a new, autoreleased not implemented exception.
  *
  * @param selector The selector which is not or not fully implemented
@@ -50,11 +48,11 @@
  * @return A new, autoreleased not implemented exception
  */
 + (instancetype)exceptionWithSelector: (SEL)selector
 			       object: (nullable id)object;
 
-- (instancetype)init OF_UNAVAILABLE;
++ (instancetype)exception OF_UNAVAILABLE;
 
 /**
  * @brief Initializes an already allocated not implemented exception.
  *
  * @param selector The selector which is not or not fully implemented
@@ -61,8 +59,10 @@
  * @param object The object which does not (fully) implement the selector
  * @return An initialized not implemented exception
  */
 - (instancetype)initWithSelector: (SEL)selector
 			  object: (nullable id)object OF_DESIGNATED_INITIALIZER;
+
+- (instancetype)init OF_UNAVAILABLE;
 @end
 
 OF_ASSUME_NONNULL_END