Fix #1322

Author: cowtowncoder

release-notes/VERSION

@@ -4,6 +4,11 @@ Project: jackson-databind
 === Releases ===
 ------------------------------------------------------------------------
 
+2.7.7 (not yet released)
+
+#1322: EnumMap keys not using enum's `@JsonProperty` values unlike Enum values
+ (reported by MichaelChambers@github)
+
 2.7.6 (23-Jul-2016)
 
 #1215: Problem with type specialization for Maps with `@JsonDeserialize(as=subtype)`

src/main/java/com/fasterxml/jackson/databind/ser/std/StdKeySerializers.java

@@ -7,6 +7,7 @@
 import com.fasterxml.jackson.core.*;
 import com.fasterxml.jackson.databind.*;
 import com.fasterxml.jackson.databind.ser.impl.PropertySerializerMap;
+import com.fasterxml.jackson.databind.util.EnumValues;
 
 @SuppressWarnings("serial")
 public class StdKeySerializers
@@ -64,6 +65,7 @@ public static JsonSerializer<Object> getStdKeySerializer(SerializationConfig con
      *
      * @since 2.7
      */
+    @SuppressWarnings("unchecked")
     public static JsonSerializer<Object> getFallbackKeySerializer(SerializationConfig config,
             Class<?> rawKeyType)
     {
@@ -78,7 +80,8 @@ public static JsonSerializer<Object> getFallbackKeySerializer(SerializationConfi
                 return new Dynamic();
             }
             if (rawKeyType.isEnum()) {
-                return new Default(Default.TYPE_ENUM, rawKeyType);
+                return EnumKeySerializer.construct(rawKeyType,
+                        EnumValues.constructFromName(config, (Class<Enum<?>>) rawKeyType));
             }
         }
         return DEFAULT_KEY_SERIALIZER;
@@ -205,4 +208,37 @@ public void serialize(Object value, JsonGenerator g, SerializerProvider provider
             g.writeFieldName((String) value);
         }
     }
+
+    /**
+     * Specialized instance to use for Enum keys, as per [databind#1322]
+     *
+     * @since 2.8
+     */
+    public static class EnumKeySerializer extends StdSerializer<Object>
+    {
+        protected final EnumValues _values;
+
+        protected EnumKeySerializer(Class<?> enumType, EnumValues values) {
+            super(enumType, false);
+            _values = values;
+        }
+
+        public static EnumKeySerializer construct(Class<?> enumType,
+                EnumValues enumValues)
+        {
+            return new EnumKeySerializer(enumType, enumValues);
+        }
+        
+        @Override
+        public void serialize(Object value, JsonGenerator g, SerializerProvider serializers)
+                throws IOException
+        {
+            if (serializers.isEnabled(SerializationFeature.WRITE_ENUMS_USING_TO_STRING)) {
+                g.writeFieldName(value.toString());
+                return;
+            }
+            Enum<?> en = (Enum<?>) value;
+            g.writeFieldName(_values.serializedValueFor(en));
+        }
+    }
 }

src/test/java/com/fasterxml/jackson/databind/ser/TestEnumSerialization.java

@@ -432,6 +432,14 @@ public void testEnumsWithJsonPropertyInSet() throws Exception
         assertEquals("[\"aleph\"]",
                 MAPPER.writeValueAsString(EnumSet.of(EnumWithJsonProperty.A)));
     }
+
+    // [databind#1322]
+    public void testEnumsWithJsonPropertyAsKey() throws Exception
+    {
+        EnumMap<EnumWithJsonProperty,String> input = new EnumMap<EnumWithJsonProperty,String>(EnumWithJsonProperty.class);
+        input.put(EnumWithJsonProperty.A, "b");
+        assertEquals("{\"aleph\":\"b\"}", MAPPER.writeValueAsString(input));
+    }
 }
 
 // [JACKSON-757], non-inner enum