Allow default enums with @JsonCreator

src/main/java/com/fasterxml/jackson/databind/deser/BasicDeserializerFactory.java

@@ -1087,7 +1087,9 @@ public JsonDeserializer<?> createEnumDeserializer(DeserializationContext ctxt,
 "Invalid `@JsonCreator` annotated Enum factory method [%s]: needs to return compatible type",
 factory.toString()));
                     }
-                    deser = EnumDeserializer.deserializerForCreator(config, enumClass, factory, valueInstantiator, creatorProps);
+                    deser = EnumDeserializer.deserializerForCreator(
+                        config, enumClass, factory, valueInstantiator, creatorProps,
+                        constructEnumResolver(enumClass, config, beanDesc));
                     break;
                 }
             }

src/main/java/com/fasterxml/jackson/databind/deser/std/EnumDeserializer.java

@@ -160,7 +160,7 @@ public EnumDeserializer(EnumResolver byNameResolver) {
     @Deprecated
     public static JsonDeserializer<?> deserializerForCreator(DeserializationConfig config,
             Class<?> enumClass, AnnotatedMethod factory) {
-        return deserializerForCreator(config, enumClass, factory, null, null);
+        return deserializerForCreator(config, enumClass, factory, null, null, null);
     }
 
     /**
@@ -172,16 +172,15 @@ public static JsonDeserializer<?> deserializerForCreator(DeserializationConfig c
      * @since 2.8
      */
     public static JsonDeserializer<?> deserializerForCreator(DeserializationConfig config,
-            Class<?> enumClass, AnnotatedMethod factory,
-            ValueInstantiator valueInstantiator, SettableBeanProperty[] creatorProps)
+             Class<?> enumClass, AnnotatedMethod factory, ValueInstantiator valueInstantiator,
+             SettableBeanProperty[] creatorProps, EnumResolver byNameResolver)
     {
         if (config.canOverrideAccessModifiers()) {
             ClassUtil.checkAndFixAccess(factory.getMember(),
                     config.isEnabled(MapperFeature.OVERRIDE_PUBLIC_ACCESS_MODIFIERS));
         }
-        return new FactoryBasedEnumDeserializer(enumClass, factory,
-                factory.getParameterType(0),
-                valueInstantiator, creatorProps);
+        return new FactoryBasedEnumDeserializer(enumClass, factory, factory.getParameterType(0),
+            valueInstantiator, creatorProps, byNameResolver);
     }
 
     /**

src/main/java/com/fasterxml/jackson/databind/deser/std/FactoryBasedEnumDeserializer.java

@@ -1,6 +1,7 @@
 package com.fasterxml.jackson.databind.deser.std;
 
 import java.io.IOException;
+import java.util.Objects;
 
 import com.fasterxml.jackson.core.JacksonException;
 import com.fasterxml.jackson.core.JsonParser;
@@ -15,6 +16,7 @@
 import com.fasterxml.jackson.databind.jsontype.TypeDeserializer;
 import com.fasterxml.jackson.databind.type.LogicalType;
 import com.fasterxml.jackson.databind.util.ClassUtil;
+import com.fasterxml.jackson.databind.util.EnumResolver;
 
 /**
  * Deserializer that uses a single-String static factory method
@@ -34,6 +36,7 @@ class FactoryBasedEnumDeserializer
     protected final JsonDeserializer<?> _deser;
     protected final ValueInstantiator _valueInstantiator;
     protected final SettableBeanProperty[] _creatorProps;
+    protected final Enum<?> _defaultValue;
 
     protected final boolean _hasArgs;
 
@@ -45,7 +48,8 @@ class FactoryBasedEnumDeserializer
     private transient volatile PropertyBasedCreator _propCreator;
 
     public FactoryBasedEnumDeserializer(Class<?> cls, AnnotatedMethod f, JavaType paramType,
-            ValueInstantiator valueInstantiator, SettableBeanProperty[] creatorProps)
+            ValueInstantiator valueInstantiator, SettableBeanProperty[] creatorProps,
+            EnumResolver enumResolver)
     {
         super(cls);
         _factory = f;
@@ -56,6 +60,13 @@ public FactoryBasedEnumDeserializer(Class<?> cls, AnnotatedMethod f, JavaType pa
         _deser = null;
         _valueInstantiator = valueInstantiator;
         _creatorProps = creatorProps;
+        _defaultValue = Objects.nonNull(enumResolver)? enumResolver.getDefaultValue() : null;
+    }
+
+    public FactoryBasedEnumDeserializer(Class<?> cls, AnnotatedMethod f, JavaType paramType,
+            ValueInstantiator valueInstantiator, SettableBeanProperty[] creatorProps)
+    {
+        this(cls, f, paramType, valueInstantiator, creatorProps, null);
     }
 
     /**
@@ -70,6 +81,7 @@ public FactoryBasedEnumDeserializer(Class<?> cls, AnnotatedMethod f)
         _deser = null;
         _valueInstantiator = null;
         _creatorProps = null;
+        _defaultValue = null;
     }
 
     protected FactoryBasedEnumDeserializer(FactoryBasedEnumDeserializer base,
@@ -80,6 +92,7 @@ protected FactoryBasedEnumDeserializer(FactoryBasedEnumDeserializer base,
         _hasArgs = base._hasArgs;
         _valueInstantiator = base._valueInstantiator;
         _creatorProps = base._creatorProps;
+        _defaultValue = base._defaultValue;
 
         _deser = deser;
     }
@@ -202,6 +215,10 @@ public Object deserialize(JsonParser p, DeserializationContext ctxt) throws IOEx
                 if (ctxt.isEnabled(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL)) {
                     return null;
                 }
+
+                if (ctxt.isEnabled(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE)) {
+                    return _defaultValue;
+                }
                 // 12-Oct-2021, tatu: Should probably try to provide better exception since
                 //   we likely hit argument incompatibility... Or can this happen?
             }

src/test/java/com/fasterxml/jackson/databind/deser/creators/EnumCreatorTest.java

@@ -125,7 +125,8 @@ public JsonDeserializer<?> findEnumDeserializer(final Class<?> type, final Deser
                 for (AnnotatedMethod am : factoryMethods) {
                     final JsonCreator creator = am.getAnnotation(JsonCreator.class);
                     if (creator != null) {
-                        return EnumDeserializer.deserializerForCreator(config, type, am, null, null);
+                        return EnumDeserializer.deserializerForCreator(
+                            config, type, am, null, null, null);
                     }
                 }
             }

src/test/java/com/fasterxml/jackson/databind/deser/enums/EnumDeserializationTest.java

@@ -161,7 +161,7 @@ static enum EnumWithDefaultAnnoAndConstructor {
     }
 
     static enum StrictEnumCreator {
-        A, B;
+        A, B, @JsonEnumDefaultValue UNKNOWN;
 
         @JsonCreator public static StrictEnumCreator fromId(String value) {
             for (StrictEnumCreator e: values()) {
@@ -453,7 +453,7 @@ public void testAllowUnknownEnumValuesReadAsNull() throws Exception
         assertNull(reader.forType(TestEnum.class).readValue(" 4343 "));
     }
 
-    // Ability to ignore unknown Enum values:
+    // Ability to ignore unknown Enum values as null:
 
     // [databind#1642]
     @Test
@@ -483,6 +483,19 @@ public void testAllowUnknownEnumValuesAsMapKeysReadAsNull() throws Exception
         assertTrue(result.map.containsKey(null));
     }
 
+    // Ability to ignore unknown Enum values as a defined default:
+
+    // [databind#4979]
+    @Test
+    public void testAllowUnknownEnumValuesReadAsDefaultWithCreatorMethod4979() throws Exception
+    {
+        ObjectReader reader = MAPPER.reader(
+            DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_USING_DEFAULT_VALUE);
+        assertEquals(
+            StrictEnumCreator.UNKNOWN,
+            reader.forType(StrictEnumCreator.class).readValue("\"NO-SUCH-VALUE\""));
+    }
+
     @Test
     public void testDoNotAllowUnknownEnumValuesAsMapKeysWhenReadAsNullDisabled() throws Exception
     {