Fix #744

release-notes/VERSION

@@ -7,6 +7,8 @@ Project: jackson-databind
 2.5.3 (not yet released)
 
 #742: Allow deserialization of `null` Object Id (missing already allowed)
+#744: Custom deserializer with parent object update failing
+ (reported by migel@github)
 #745: EnumDeserializer.deserializerForCreator fails when used to deserialize a Map key
  (contributed by John M)
 

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

@@ -138,12 +138,14 @@ public class ObjectReader
      */
 
     /**
-     * Root-level cached deserializers
+     * Root-level cached deserializers.
+     * Passed by {@link ObjectMapper}, shared with it.
      */
     final protected ConcurrentHashMap<JavaType, JsonDeserializer<Object>> _rootDeserializers;
 
     /**
      * Cache for root names used when root-wrapping is enabled.
+     * Passed by {@link ObjectMapper}, shared with it.
      */
     protected final RootNameLookup _rootNames;
 
@@ -1471,7 +1473,7 @@ protected JsonNode _bindAsTree(JsonParser jp) throws IOException
             result = NullNode.instance;
         } else {
             DeserializationContext ctxt = createDeserializationContext(jp, _config);
-            JsonDeserializer<Object> deser = _findRootDeserializer(ctxt, JSON_NODE_TYPE);
+            JsonDeserializer<Object> deser = _findTreeDeserializer(ctxt);
             if (_unwrapRoot) {
                 result = (JsonNode) _unwrapAndDeserialize(jp, ctxt, JSON_NODE_TYPE, deser);
             } else {
@@ -1569,6 +1571,24 @@ protected JsonDeserializer<Object> _findRootDeserializer(DeserializationContext
         return deser;
     }
 
+    /**
+     * @since 2.6
+     */
+    protected JsonDeserializer<Object> _findTreeDeserializer(DeserializationContext ctxt)
+        throws JsonMappingException
+    {
+        JsonDeserializer<Object> deser = _rootDeserializers.get(JSON_NODE_TYPE);
+        if (deser == null) {
+            // Nope: need to ask provider to resolve it
+            deser = ctxt.findRootValueDeserializer(JSON_NODE_TYPE);
+            if (deser == null) { // can this happen?
+                throw new JsonMappingException("Can not find a deserializer for type "+JSON_NODE_TYPE);
+            }
+            _rootDeserializers.put(JSON_NODE_TYPE, deser);
+        }
+        return deser;
+    }
+
     /**
      * Method called to locate deserializer ahead of time, if permitted
      * by configuration. Method also is NOT to throw an exception if

src/test/java/com/fasterxml/jackson/databind/convert/TestUpdateValue.java

@@ -1,10 +1,13 @@
 package com.fasterxml.jackson.databind.convert;
 
+import java.io.IOException;
 import java.util.*;
 
 import com.fasterxml.jackson.annotation.JsonView;
-import com.fasterxml.jackson.databind.BaseMapTest;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.core.*;
+import com.fasterxml.jackson.databind.*;
+import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
+import com.fasterxml.jackson.databind.module.SimpleModule;
 
 import static org.junit.Assert.assertArrayEquals;
 
@@ -44,7 +47,40 @@ public class Updateable {
         @JsonView(TextView.class)
         public String str;
     }
-
+
+    // for [databind#744]
+    static class DataA {
+        public int i = 1;
+        public int j = 2;
+
+    }
+
+    static class DataB {
+        public DataA da = new DataA();
+        public int k = 3;
+    }
+
+    static class DataADeserializer extends StdDeserializer<DataA> {
+        private static final long serialVersionUID = 1L;
+
+        DataADeserializer() {
+            super(DataA.class);
+        }
+
+        public DataA deserialize(JsonParser jp, DeserializationContext ctxt)
+                throws JsonProcessingException, IOException {
+            if (jp.getCurrentToken() != JsonToken.START_OBJECT) {
+                throw ctxt.mappingException("Wrong current token, expected START_OBJECT, got: "
+                        +jp.getCurrentToken());
+            }
+            /*JsonNode node =*/ jp.readValueAsTree();
+
+            DataA da = new DataA();
+            da.i = 5;
+            return da;
+        }
+    }
+
     /*
     /********************************************************
     /* Unit tests
@@ -146,4 +182,45 @@ public void testUpdatingWithViews() throws Exception
         assertEquals(100, bean.num);
         assertEquals("foobar", bean.str);
     }
+
+    // [databind#744]
+    public void testIssue744() throws IOException
+    {
+        ObjectMapper mapper = new ObjectMapper();
+        SimpleModule module = new SimpleModule();
+        module.addDeserializer(DataA.class, new DataADeserializer());
+        mapper.registerModule(module);
+
+        DataB db = new DataB();
+        db.da.i = 11;
+        db.k = 13;
+        String jsonBString = mapper.writeValueAsString(db);
+        JsonNode jsonBNode = mapper.valueToTree(db);
+
+        // create parent
+        DataB dbNewViaString = mapper.readValue(jsonBString, DataB.class);
+        assertEquals(5, dbNewViaString.da.i);
+        assertEquals(13, dbNewViaString.k);
+
+        DataB dbNewViaNode = mapper.treeToValue(jsonBNode, DataB.class);
+        assertEquals(5, dbNewViaNode.da.i);
+        assertEquals(13, dbNewViaNode.k);
+
+        // update parent
+        DataB dbUpdViaString = new DataB();
+        DataB dbUpdViaNode = new DataB();
+
+        assertEquals(1, dbUpdViaString.da.i);
+        assertEquals(3, dbUpdViaString.k);
+        mapper.readerForUpdating(dbUpdViaString).readValue(jsonBString);
+        assertEquals(5, dbUpdViaString.da.i);
+        assertEquals(13, dbUpdViaString.k);
+
+        assertEquals(1, dbUpdViaNode.da.i);
+        assertEquals(3, dbUpdViaNode.k);
+
+        mapper.readerForUpdating(dbUpdViaNode).readValue(jsonBNode);
+        assertEquals(5, dbUpdViaNode.da.i);
+        assertEquals(13, dbUpdViaNode.k);
+    }
 }