Fix a minor problem with @JsonNaming not recognizing default value ("no naming")

Author: cowtowncoder

release-notes/VERSION

@@ -10,6 +10,7 @@ Project: jackson-databind
  (reported by Antibrumm@github)
 #989: Deserialization from "{}" to java.lang.Object causes "out of END_OBJECT token" error
  (reported by Ievgen P)
+- Fix a minor problem with `@JsonNaming` not recognizing default value
 
 2.6.3 (12-Oct-2015)
 

src/main/java/com/fasterxml/jackson/databind/annotation/JsonNaming.java

@@ -7,6 +7,9 @@
 /**
  * Annotation that can be used to indicate a {@link PropertyNamingStrategy}
  * to use for annotated class. Overrides the global (default) strategy.
+ * Note that if the {@link #value} property is omitted, its default value
+ * means "use default naming" (that is, no alternate naming method is used).
+ * This can be used as an override with mix-ins.
  * 
  * @since 2.1
  */

src/main/java/com/fasterxml/jackson/databind/introspect/POJOPropertiesCollector.java

@@ -1007,6 +1007,11 @@ private PropertyNamingStrategy _findNamingStrategy()
                     +namingDef.getClass().getName()+"; expected type PropertyNamingStrategy or Class<PropertyNamingStrategy> instead");
         }
         Class<?> namingClass = (Class<?>)namingDef;
+        // 09-Nov-2015, tatu: Need to consider pseudo-value of STD, which means "use default"
+        if (namingClass == PropertyNamingStrategy.class) {
+            return null;
+        }
+        
         if (!PropertyNamingStrategy.class.isAssignableFrom(namingClass)) {
             throw new IllegalStateException("AnnotationIntrospector returned Class "
                     +namingClass.getName()+"; expected Class<PropertyNamingStrategy>");

src/test/java/com/fasterxml/jackson/databind/introspect/TestNamingStrategyStd.java

@@ -96,6 +96,20 @@ public static class ClassWithObjectNodeField {
         public ObjectNode json;
     }    
 
+    static class ExplicitBean {
+        @JsonProperty("firstName")
+        String userFirstName = "Peter";
+        @JsonProperty("lastName")
+        String userLastName = "Venkman";
+        @JsonProperty
+        String userAge = "35";
+    }
+
+    @JsonNaming()
+    static class DefaultNaming {
+        public int someValue = 3;
+    }
+    
     /*
     /**********************************************************
     /* Set up
@@ -316,4 +330,12 @@ public void testNamingWithObjectNode() throws Exception
         assertEquals(2, result.json.size());
         assertEquals("bing", result.json.path("baz").asText());
     }
+
+    // Also verify that "no naming strategy" should be ok
+    public void testExplicitNoNaming() throws Exception
+    {
+        ObjectMapper mapper = objectMapper();
+        String json = mapper.writeValueAsString(new DefaultNaming());
+        assertEquals(aposToQuotes("{'someValue':3}"), json);
+    }
 }