Backport #703 fix by Francisco

release-notes/CREDITS

@@ -207,3 +207,11 @@ Ludevik@github:
 Antibrumm@github:
   * Reported #691: Jackson 2.5.0. NullSerializer for MapProperty failing
    (2.5.2)
+
+ Shumpei Akai (flexfrank@github)
+  * Reported #703: Multiple calls to ObjectMapper#canSerialize(Object.class) returns different values
+   (2.5.2)
+
+Francisco A. Lozano (flozano@github)
+  * Contributed fix for #703 (see above)
+   (2.5.2)

release-notes/VERSION

@@ -8,6 +8,8 @@ Project: jackson-databind
 
 #691: NullSerializer for MapProperty failing when using polymorphic handling
  (reported by Antibrumm@github)
+#703: Multiple calls to ObjectMapper#canSerialize(Object.class) returns different values
+ (reported by flexfrank@github)
 
 2.5.1 (06-Feb-2015)
 

src/main/java/com/fasterxml/jackson/databind/SerializerProvider.java

@@ -1087,16 +1087,16 @@ protected JsonSerializer<Object> _findExplicitUntypedSerializer(Class<?> runtime
             ser = _serializerCache.untypedValueSerializer(runtimeType);
             if (ser == null) {
                 ser = _createAndCacheUntypedSerializer(runtimeType);
-                /* 18-Sep-2014, tatu: This is unfortunate patch over related change
-                 *    that pushes creation of "unknown type" serializer deeper down
-                 *    in BeanSerializerFactory; as a result, we need to "undo" creation
-                 *    here.
-                 */
-                if (isUnknownTypeSerializer(ser)) {
-                    return null;
-                }
             }
         }
+        /* 18-Sep-2014, tatu: This is unfortunate patch over related change
+         *    that pushes creation of "unknown type" serializer deeper down
+         *    in BeanSerializerFactory; as a result, we need to "undo" creation
+         *    here.
+         */
+        if (isUnknownTypeSerializer(ser)) {
+            return null;
+        }
         return ser;
     }
 

src/test/java/com/fasterxml/jackson/databind/TestObjectMapper.java

@@ -185,4 +185,13 @@ public void testAnnotationIntrospectorCopyin()
         assertEquals(MyAnnotationIntrospector.class,
                 m2.getSerializationConfig().getAnnotationIntrospector().getClass());
     }
+
+    // For [databind#703]
+    public void testNonSerializabilityOfObject()
+    {
+        ObjectMapper m = new ObjectMapper();
+        assertFalse(m.canSerialize(Object.class));
+        // but this used to pass, incorrectly
+        assertFalse(m.canSerialize(Object.class));
+    }
 }