Fixed #1161

release-notes/VERSION

@@ -11,6 +11,9 @@ Project: jackson-databind
  (reported by Xavi T)
 #1154: @JsonFormat.pattern on dates is now ignored if shape is not explicitely provided
  (reported by Yoann R)
+#1161: `DeserializationFeature.READ_ENUMS_USING_TO_STRING` not dynamically
+  changeable with 2.7
+ (reported by asa-git@github)
 - Minor fixes to `AnnotationIntrospector.findEnumValues()` to correct problems with
   merging of explicit enum value names.
 

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

@@ -1252,7 +1252,8 @@ public JsonDeserializer<?> createEnumDeserializer(DeserializationContext ctxt,
             }
             // Need to consider @JsonValue if one found
             if (deser == null) {
-                deser = new EnumDeserializer(constructEnumResolver(enumClass, config, beanDesc.findJsonValueMethod()));
+                deser = new EnumDeserializer(constructEnumResolver(enumClass,
+                        config, beanDesc.findJsonValueMethod()));
             }
         }
 
@@ -1436,7 +1437,6 @@ private KeyDeserializer _createEnumKeyDeserializer(DeserializationContext ctxt,
                 return StdKeyDeserializers.constructDelegatingKeyDeserializer(config, type, valueDesForKey);
             }
         }
-
         EnumResolver enumRes = constructEnumResolver(enumClass, config, beanDesc.findJsonValueMethod());
         // May have @JsonCreator for static factory method:
         final AnnotationIntrospector ai = config.getAnnotationIntrospector();
@@ -1919,10 +1919,8 @@ protected EnumResolver constructEnumResolver(Class<?> enumClass,
             }
             return EnumResolver.constructUnsafeUsingMethod(enumClass, accessor);
         }
-        // May need to use Enum.toString()
-        if (config.isEnabled(DeserializationFeature.READ_ENUMS_USING_TO_STRING)) {
-            return EnumResolver.constructUnsafeUsingToString(enumClass);
-        }
+        // 14-Mar-2016, tatu: We used to check `DeserializationFeature.READ_ENUMS_USING_TO_STRING`
+        //   here, but that won't do: it must be dynamically changeable...
         return EnumResolver.constructUnsafe(enumClass, config.getAnnotationIntrospector());
     }
 

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

@@ -27,18 +27,26 @@ public class EnumDeserializer
     /**
      * @since 2.6
      */
-    protected final CompactStringObjectMap _enumLookup;
+    protected Object[] _enumsByIndex;
 
     /**
-     * @since 2.6
+     * @since 2.7.3
      */
-    protected Object[] _enumsByIndex;
+    protected final CompactStringObjectMap _lookupByName;
 
-    public EnumDeserializer(EnumResolver res)
+    /**
+     * Alternatively, we may need a different lookup object if "use toString"
+     * is defined.
+     *
+     * @since 2.7.3
+     */
+    protected CompactStringObjectMap _lookupByToString;
+
+    public EnumDeserializer(EnumResolver byNameResolver)
     {
-        super(res.getEnumClass());
-        _enumLookup = res.constructLookup();
-        _enumsByIndex = res.getRawEnums();
+        super(byNameResolver.getEnumClass());
+        _lookupByName = byNameResolver.constructLookup();
+        _enumsByIndex = byNameResolver.getRawEnums();
     }
 
     /**
@@ -80,10 +88,12 @@ public Object deserialize(JsonParser p, DeserializationContext ctxt) throws IOEx
 
         // Usually should just get string value:
         if (curr == JsonToken.VALUE_STRING || curr == JsonToken.FIELD_NAME) {
-            String name = p.getText();
-            Object result = _enumLookup.find(name);
+            CompactStringObjectMap lookup = ctxt.isEnabled(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
+                    ? _getToStringLookup() : _lookupByName;
+            final String name = p.getText();
+            Object result = lookup.find(name);
             if (result == null) {
-                return _deserializeAltString(p, ctxt, name);
+                return _deserializeAltString(p, ctxt, lookup, name);
             }
             return result;
         }
@@ -106,8 +116,14 @@ public Object deserialize(JsonParser p, DeserializationContext ctxt) throws IOEx
         return _deserializeOther(p, ctxt);
     }
 
+    /*
+    /**********************************************************
+    /* Internal helper methods
+    /**********************************************************
+     */
+
     private final Object _deserializeAltString(JsonParser p, DeserializationContext ctxt,
-            String name) throws IOException
+            CompactStringObjectMap lookup, String name) throws IOException
     {
         name = name.trim();
         if (name.length() == 0) {
@@ -133,7 +149,7 @@ private final Object _deserializeAltString(JsonParser p, DeserializationContext
         }
         if (!ctxt.isEnabled(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL)) {
             throw ctxt.weirdStringException(name, _enumClass(),
-                    "value not one of declared Enum instance names: "+_enumLookup.keys());
+                    "value not one of declared Enum instance names: "+lookup.keys());
         }
         return null;
     }
@@ -169,6 +185,21 @@ protected Class<?> _enumClass() {
         return handledType();
     }
 
+    protected CompactStringObjectMap _getToStringLookup()
+    {
+        CompactStringObjectMap lookup = _lookupByToString;
+        // note: exact locking not needed; all we care for here is to try to
+        // reduce contention for the initial resolution
+        if (lookup == null) {
+            synchronized (this) {
+                lookup = EnumResolver.constructUnsafeUsingToString(_enumClass())
+                        .constructLookup();
+            }
+            _lookupByToString = lookup;
+        }
+        return lookup;
+    }
+
     /*
     /**********************************************************
     /* Additional helper classes

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

@@ -117,7 +117,7 @@ public static StdKeyDeserializer forType(Class<?> raw)
 
     @Override
     public Object deserializeKey(String key, DeserializationContext ctxt)
-        throws IOException, JsonProcessingException
+        throws IOException
     {
         if (key == null) { // is this even legal call?
             return null;
@@ -318,13 +318,21 @@ final static class EnumKD extends StdKeyDeserializer
     {
         private static final long serialVersionUID = 1L;
 
-        protected final EnumResolver _resolver;
+        protected final EnumResolver _byNameResolver;
 
         protected final AnnotatedMethod _factory;
 
+        /**
+         * Lazily constructed alternative in case there is need to
+         * use 'toString()' method as the source.
+         *
+         * @since 2.7.3
+         */
+        protected EnumResolver _byToStringResolver;
+
         protected EnumKD(EnumResolver er, AnnotatedMethod factory) {
             super(-1, er.getEnumClass());
-            _resolver = er;
+            _byNameResolver = er;
             _factory = factory;
         }
 
@@ -338,12 +346,26 @@ public Object _parse(String key, DeserializationContext ctxt) throws JsonMapping
                     ClassUtil.unwrapAndThrowAsIAE(e);
                 }
             }
-            Enum<?> e = _resolver.findEnum(key);
+            EnumResolver res = ctxt.isEnabled(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
+                    ? _getToStringResolver() : _byNameResolver;
+            Enum<?> e = res.findEnum(key);
             if ((e == null) && !ctxt.getConfig().isEnabled(DeserializationFeature.READ_UNKNOWN_ENUM_VALUES_AS_NULL)) {
-                throw ctxt.weirdKeyException(_keyClass, key, "not one of values for Enum class");
+                throw ctxt.weirdKeyException(_keyClass, key, "not one of values excepted for Enum class: "
+                        +res.getEnumIds());
             }
             return e;
         }
+
+        private EnumResolver _getToStringResolver()
+        {
+            EnumResolver res = _byToStringResolver;
+            if (res == null) {
+                synchronized (this) {
+                    res = EnumResolver.constructUnsafeUsingToString(_byNameResolver.getEnumClass());
+                }
+            }
+            return res;
+        }
     }
 
     /**

src/main/java/com/fasterxml/jackson/databind/util/EnumResolver.java

@@ -1,11 +1,11 @@
 package com.fasterxml.jackson.databind.util;
 
-import com.fasterxml.jackson.databind.AnnotationIntrospector;
-
 import java.lang.reflect.Method;
 import java.util.*;
 
-/**
+import com.fasterxml.jackson.databind.AnnotationIntrospector;
+
+    /**
  * Helper class used to resolve String values (either JSON Object field
  * names or regular String values) into Java Enum instances.
  */
@@ -62,7 +62,7 @@ public static EnumResolver constructUsingToString(Class<Enum<?>> enumCls)
             map.put(e.toString(), e);
         }
         return new EnumResolver(enumCls, enumValues, map);
-    }    
+    }
 
     public static EnumResolver constructUsingMethod(Class<Enum<?>> enumCls,
             Method accessor)
@@ -146,6 +146,13 @@ public List<Enum<?>> getEnums() {
         }
         return enums;
     }
+
+    /**
+     * @since 2.7.3
+     */
+    public Collection<String> getEnumIds() {
+        return _enumsById.keySet();
+    }
 
     public Class<Enum<?>> getEnumClass() { return _enumClass; }
 

src/test/java/com/fasterxml/jackson/databind/deser/TestEnumDeserialization.java

@@ -2,10 +2,7 @@
 
 import java.io.IOException;
 import java.math.BigDecimal;
-import java.util.Collection;
-import java.util.EnumMap;
-import java.util.EnumSet;
-import java.util.Map;
+import java.util.*;
 import java.util.concurrent.TimeUnit;
 
 import com.fasterxml.jackson.annotation.*;
@@ -167,6 +164,16 @@ public String toString() {
         ;
     }
 
+    // [databind#1161]
+    enum Enum1161 {
+        A, B, C;
+
+        @Override
+        public String toString() {
+            return name().toLowerCase();
+        };
+    }
+
     /*
     /**********************************************************
     /* Tests
@@ -481,4 +488,22 @@ public void testEnumWithJsonPropertyRename() throws Exception
         assertSame(EnumWithPropertyAnno.B, result[0]);
         assertSame(EnumWithPropertyAnno.A, result[1]);
     }
-}
+
+    // [databind#1161], unable to switch READ_ENUMS_USING_TO_STRING
+    public void testDeserWithToString1161() throws Exception
+    {
+        Enum1161 result = MAPPER.readerFor(Enum1161.class)
+                .readValue(quote("A"));
+        assertSame(Enum1161.A, result);
+
+        result = MAPPER.readerFor(Enum1161.class)
+                .with(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
+                .readValue(quote("a"));
+        assertSame(Enum1161.A, result);
+
+        // and once again, going back to defaults
+        result = MAPPER.readerFor(Enum1161.class)
+                .without(DeserializationFeature.READ_ENUMS_USING_TO_STRING)
+                .readValue(quote("A"));
+        assertSame(Enum1161.A, result);
+    }}